Answer:
THE VOLUME OF THE NITROGEN GAS AT 2.5 MOLES , 1.75 ATM AND 475 K IS 55.64 L
Explanation:
Using the ideal gas equation
PV = nRT
P = 1.75 atm
n = 2.5 moles
T = 475 K
R = 0.082 L atm/mol K
V = unknown
Substituting the variables into the equation we have:
V = nRT / P
V = 2.5 * 0.082 * 475 / 1.75
V = 97.375 / 1.75
V = 55.64 L
The volume of the 2.5 moles of nitrogen gas exerted by 1.75 atm at 475 K is 55.64 L
Consider the reaction of 1-butanol with K2Cr2O7, H2SO4, heat. Draw only the organic product derived from 1-butanol.
Answer:
Butanoic acid.
Explanation:
Hello,
In this case, when a primary alcohol such as 1-butanol (OH is bonded to a primary carbon) is oxidized in the presence of a strong oxidizing media such as potassium dichromate (K2Cr2O7) and sulfuric acid, the stepwise oxidation goes to the corresponding aldehyde with a further oxidation to the corresponding carboxylic acid:
[tex]R-CH_2-OH\longrightarrow R-COH\longrightarrow R-COOH[/tex]
Therefore, on the attached picture you can find that the formed aldehyde is butanal and the inly organic product, due to the strong oxidizing media is finally butanoic acid.
Best regards.
The following compounds have similar molecular weights. Which has the highest boiling point?
A. CH3OCH3
B. C2H5OH
C. CH3CH2CH3
D. CH3CH=O
Answer:
[tex]\Huge \boxed{\mathrm{C_2H_5OH}}[/tex]
Explanation:
CH₃OCH₃ (Dimethyl ether) has a boiling point of -23 °C
C₂H₅OH (Ethanol) has a boiling point of 78.37 °C
CH₃CH₂CH₃ (Propane) has a boiling point of -42 °C
CH₃CHO (Acetaldehyde) has a boiling point of 20.2 °C
C₂H₅OH (Ethanol) has the highest boiling point.
a) A reaction container holds 5.33 g of P4 and 3.77 g of O2 and reaction A occurs. If enough oxygen is available then the P4O6 reacts further to undergo reaction B. What is the limiting reactant for the formation of P4O6? b) What mass of P4O6 is produced (theoretical yield in grams)? c) If 7.12g of P4O6 were obtained what is the percent yield? d) Will reaction B occur? Why or why not? What mass of excess reactant is left in the reaction container?
The given question is incomplete, the complete question is:
Balance the following chemical equations: A) P4+ O2 → P406 B) _P406+ LO2 → P4010 a) A reaction container holds 5.33 g of P4 and 3.77 g of O2 and reaction A occurs. If enough oxygen is available then the P406 reacts further to undergo reaction B. What is the limiting reactant for the formation of P406? b) What mass of P406 is produced (theoretical yield in grams)? c) If 7.12g of P406 were obtained what is the percent yield? d) Will reaction B occur? Why or why not? What mass of excess reactant is left in the reaction container?
Answer:
The balanced reaction will be,
A) P₄ + 3O₂ ⇒ P₄O₆
B) P₄O₆ + 2O₂ ⇒ P₄O₆
a) Based on the given information, the reaction container holds 5.33 grams of P₄ and 3.77 grams of oxygen. Thus, the moles of P₄ will be,
Moles = mass of P₄/Molar mass of P₄ = 5.33 grams/124 g/mole = 0.043 mole
Now the moles of O₂ will be,
Moles = mass of O₂/Molar mass of O₂ = 3.77 grams/32 g/mol = 0.112 mole
Now the moles of P₄O₆ formed when 0.043 moles of P₄ react completely will be = 1/1 × 0.043 = 0.043 mole of P₄O₆
Similarly, the moles of P₄O₆ formed, when 0.112 moles of O₂ react completely will be = 1/3 × 0.112 = 0.0373 mole of P₄O₆
Thus, from the analysis, the maximum moles of P₄O₆ formed will be 0.0373 moles. Therefore, oxygen will be the limiting reagent, which will react completely in the reaction.
b) From the above findings, the maximum moles of P₄O₆ produced is 0.0373 mole. Thus, the theoretical yield of P₄O₆ produced will be,
= Moles of P₄O₆ × Molar mass of P₄O₆
Theoretical yield = 0.0373 mole × 220 g/mole = 8.206 grams
c) Based on the given information, the actual mass of P₄O₆ produced is 7.12 grams.
Hence, percent yield = Actual yield/Theoretical yield * 100
= 7.12/8.206 × 100 = 86.77 %
d) In the given case, reaction B will not take place. This is due to the fact that oxygen is not left for reaction B, which was the limiting regent for reaction A. Here P₄ is the excess reactant, which was left in the reaction.
The initial moles of P₄ is 0.043, O₂ is 0.112, and P₄O₆ is O. The final moles of P₄ is 0.043 -1/3 × 0.112 = 0.0057 mole, O₂ is 0, and P₄O₆ is 0.0373 mole.
Thus, moles of P₄ left is 0.0057 mole. Hence, the mass of P₄ left will be,
= 0.0057 mole × Molar mass of P₄
= 0.0057 mole × 124 g/mole = 0.7068 grams.
5. Which of the following statements about the modern
Quantum model of the atom is TRUE?
a. Electron clouds are formed by electron movement.
b. Only protons form the nucleus.
c. Protons and electrons form the nucleus.
d. Neutrons in the nucleus have a positive charge.
What theory offers a description of submicroscopic properties of matter and connects them to observable macroscopic properties?
Answer:
Kinetic Molecular theory of matter
Explanation:
Answer:
The kinetic molecular theory of matter offers a description of the microscopic properties of atoms (or molecules) and their interactions, leading to observable macroscopic properties (such as pressure, volume, temperature).
Explanation:
Which of the following solutions would have the highest osmotic pressure?
a) 0.35 m CH4N2O
b) pure water
c) 0.15 m Zn(CH3COO)2
d) 0.10 m Cr2(SO4)3
e) 0.16 m BaI2
Answer:
Option d. 0.10 m Cr₂(SO₄)₃
Explanation:
Formula for the osmotic pressure is determined as:
π = M . R . T . i
So you have to take account the i (Van't Hoff factor, numbers of ions dissolved)
CH₄N₂O → 0.35 mUrea is an organic compound, so the i value is 1
H₂O → The i is also 1Zn(CH₃COO)₂ → 0.15 mZync acetate can be dissociated:
Zn(CH₃COO)₂ → 1Zn²⁺ + 2CH₃COO⁻
In this case, the i is 3. (you see, the stoichiometry of ions)
Cr₂(SO₄)₃ → 0.10 m
Chromium sulfate is dissociated:
Cr₂(SO₄)₃ → 2Cr³⁺ + 3SO₄⁻²
i = 5
BaI₂ → 0.16 m
BaI₂ → 1Ba²⁺ + 2I⁻
i = 3
A 0.56 M solution of AlCl₃ is determined to have a concentration of particles of 1.79 M. What is the van't Hoff factor for AlCl₃?
Answer:
Van't Hoff factor for AlCl₃ = 3 (Approx)
Explanation:
Given:
Number of observed particular = 1.79 M
Number of theoretical particular = 0.56 M
Find:
Van't Hoff factor for AlCl₃
Computation:
Van't Hoff factor for AlCl₃ = Number of observed particular / Number of theoretical particular
Van't Hoff factor for AlCl₃ = 1.79 M / 0.56 M
Van't Hoff factor for AlCl₃ = 3.19
Van't Hoff factor for AlCl₃ = 3 (Approx)
The Van't Hoff factor for the AlCl₃ solution is 3
What is Van't Hoff factor?Van't Hoff factor describes the number of ions in a solution. The Van't Hoff factor for non-electrolyte is always 1 while it varies for ionic solutions.
How to determine the Van't Hoff factorFrom the question given above, the following data were obtained:
Actual molarity of particular = 1.79 MTheoretical molarity of particular = 0.56 MVan't Hoff factor for AlCl₃ =?Van't Hoff factor = Actual molarity / Theoretical molarity
Van't Hoff factor for AlCl₃ = 1.79 / 0.56
Van't Hoff factor for AlCl₃ ≈ 3
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Give an example of an element and an example of a compound.
Answer:
an element is a atom like titanium and a compound is like a water, glucose, alcohol and salt
Explanation:
the titanium is a element and water, glucose, alcohol, and salt those are a compound
hich of these processes are chemical reactions? boiling an egg crushing spices vegetables rotting chopping vegetables dew forming
Answer:
Boiling an egg is a chemical reaction
Vegetable rotting is a chemical reaction.
Chemical reaction: In this Chemical reaction takes place and new products is formed.
Explanation:
Calculate the Ka for the following acid. Determine if it is a strong or weak acid.
HNO2(aq) dissolves in aqueous solution to form H+(aq) and NO2−(aq). At equilibrium, the concentrations of each of the
species are as follows:
[HNO2]=0.68M
[H+]=0.022M
[NO2−]=0.022M
Calculate the for the following acid. Determine if it is a strong or weak acid.
dissolves in aqueous solution to form and . At equilibrium, the concentrations of each of the species are as follows:
a) Ka=7.1×10−4; This is a weak acid because the acid is not completely dissociated in solution.
b) Ka=1405; This is a strong acid because the Ka is very large.
c) Ka=1405; This is a weak acid because the acid is not completely dissociated in solution.
d) Ka=7.1×10−4; This is a strong acid because the acid is completely dissociated in aqueous solution.
Answer:
a) Ka= 7.1 × 10⁻⁴; This is a weak acid because the acid is not completely dissociated in solution.
Explanation:
Step 1: Write the dissociation reaction for nitrous acid
HNO₂(aq) ⇄ H⁺(aq) and NO₂⁻(aq)
Step 2: Calculate the acid dissociation constant
Ka = [H⁺] × [NO₂⁻] / [HNO₂]
Ka = 0.022 × 0.022 / 0.68
Ka = 7.1 × 10⁻⁴
Step 3: Determine the strength of the acid
Since Ka is very small, nitrous acid is a weak acid, not completely dissociated in solution.
The quantity of antimony in an ore can be determined by an oxidation-reduction titration with an oxidizing agent. The ore is dissolved in hot, concentrated acid and passed over a reducing agent so that all the antimony is in the form Sb3 (aq). The Sb3 (aq) is completely oxidized by an aqueous solution of BrO3–(aq). Complete and balance the equation for this reaction in acidic solution.
6H+ +Bro3- +3Sb3+----------> Br- +3Sb5+3H2O
Answer:
3Sb^3+(aq) + BrO3^-(aq) + 6H^+(aq)----->3Sb^5+(aq) + Br^-(aq) 3H2O(l)
Explanation:
When we want to balance redox reaction equations, we must ensure that the number of electrons lost in the oxidation half reaction equation is equal to the number of electrons gained in the reduction half reaction equation.
After we have done this, we can now write the overall balanced reaction equation without including the number of electrons lost or gained. Hence;
Oxidation half equation;
3Sb^3+(aq) -----> 3Sb^5+(aq) +6e
Reduction half equation;
BrO3^-(aq) + 6H^+(aq) + 6e ----> Br^-(aq) 3H2O(l)
Overall balanced reaction equation;
3Sb^3+(aq) + BrO3^-(aq) + 6H^+(aq)----->3Sb^5+(aq) + Br^-(aq) 3H2O(l)
list any five items that can be found in a Science portfolio
Answer:
physical projects
Journal entries
Materials
Lab reports
Artworks
Explanation:
Definition of a Portfolio:
Portfolio can be defined as a physical collection of student work that includes materials such as written assignments, completed tests, artwork, lab reports, physical projects and other material evidence of learning progress and academic accomplishment, including awards and honors,
A portfolio is a long-term form of self reflection and assessment that students do together.
Portfolios are a great way to demonstrate the competencies you would list on a resume or talk about in a science interview
A buffer solution is 0.413 M in HF and 0.237 M in KF. If Ka for HF is 7.2×10-4, what is the pH of this buffer solution?
Answer:
2.90
Explanation:
Any buffer system can be described with the reaction:
[tex]HA~->~H^+~+~A^-[/tex]
Where [tex]HA[/tex] is the acid and [tex]A^-[/tex] is the base. Additionally, the calculation of the pH of any buffer system can be made with the Henderson-Hasselbach equation:
[tex]pH=pKa~+~Log\frac{[A^-]}{[HA]}[/tex]
With all this in mind, we can write the reaction for our buffer system:
[tex]HF~->~H^+~+~F^-[/tex]
In this case, the acid is [tex]HF[/tex] with a concentration of 0.413 M and the base is [tex]F^-[/tex] with a concentration of 0.237 M. We can calculate the pKa value if we do the "-Log Ka", so:
[tex]pKa~=~-Log(7.2X10^-^4)=~3.14[/tex]
Now, we can plug the values into the Henderson-Hasselbach
[tex]pH=~3.14~+~Log(\frac{[0.237~M]}{[0.413~M]})~=~2.90[/tex]
The pH value would be 2.90
I hope it helps!
Al2O3 (s) + 6 NaOH (aq) + 12HF (g) → 2 Na3AlF6 (s) + 9 H2O (l) In an experiment; 6.55 g Al2O3 and excess HF were dissolved in 1.75 L of 0.15 M NaOH. If 20 g Na3AlF6was obtained, a Which one is the limiting reagent? b What is the actual yield? c What is the theoretical yield? d What is the percent yield for this experiment?
Answer:
A. NaOH
B. 20 g
C. 18.4 g
D. 108%
Explanation:
Al₂O₃ + 6 NaOH + 12 HF ⇒ 2 Na₃AlF₆ + 9 H₂O
A. Since you have excess HF, this is not the limiting reagent. The two possibilities are Al₂O₃ and NaOH. Find out how many moles you have of each. Then, use the mole ratio in the chemical equation to find out how much product each reagent can produce. The reagent the produces the least is the limiting reagent. The molar mass of Al₂O₃ is 101.96 g/mol.
(6.55 g Al₂O₃)/(101.96 g/mol Al₂O₃) = 0.06424 mol Al₂O₃
(0.06424 mol Al₂O₃) × (2 mol Na₃AlF₆/1 mol Al₂O₃) = 0.12848 mol Na₃AlF₆
(1.75 L NaOH) × (0.15 M NaOH) = 0.2625 mol NaOH
(0.2625 mol NaOH) × (2 mol Na₃AlF₆/6 mol NaOH) = 0.0875 mol Na₃AlF₆
NaOH produces less product, making it the limiting reagent.
B. The actual yield is 20 g. This information is given in the problem.
C. Since you know how much product you will get, convert moles of Na₃AlF₆ to grams to find actual yield. Use the value found for Na₃AlF₆ that you got from the limiting reagent. The molar mass is 209.94 g/mol.
(0.0875 mol Na₃AlF₆) × (209.94 g/mol Na₃AlF₆) = 18.4 g Na₃AlF₆
D. To find the percent yield, divide the actual yield by the theoretical yield and multiply by 100%.
(20 g)/(18.4 g) × 100% = 108%
If your percent yield is greater than 100% when performing a reaction, there has been a mistake somewhere. Either you recorded the numbers incorrectly or there has been some human error in your experiment. This might be the right answer for this problem, but you might want to double check to make sure the numbers you gave me were right.
Which of the following compounds will have the highest molar solubility in pure water?
a. PbS, Ksp = 9.04 × 10^-29
b. CuS, Ksp = 1.27 × 10^-36
c. Al(OH)3, Ksp = 3 × 10^-34
d. ZnS, Ksp = 1.6 × 10^-24
e. Ag2S, Ksp = 8 × 10^-4
Answer:
ZnS, Ksp=2.0×10−25
Explanation:
The Ksp is a constant that let us know the capacity of the compound to easily dissociates in water. The higher the Ksp, the more soluble the compound is. In the exercise giving, the highest Ksp is 2.0×10−25, that means ZnS will dilutes easily than others
An insoluble solid is placed in water and the system allowed to reach equilibrium. The ratio of the rate at which ions join the solution and the rate at which ions join the lattice will be:
Answer:
One.
Explanation:
Hello,
In this case, the equilibrium condition is characterized by the equality of the rates at which a process happen and the contrary process happen, so its ratio is 1. For instance, a chemical reaction at equilibrium will have a contant ratio of the velocity at which the products are formed and the reactants consumed
However, for the described insoluble solid that is allowed the reach equilibrium, the ratio of the rate at which ions join the solution and the rate at which ions join the lattice will be one since it reaches an equilibrium state.
Best regards.
If this is a p1000 micropipette, then this is set to dispense [ Select]ul. If this is a p10
micropipette, then this is set to dispense [ Select ]ul.
Answer:
1000 µL; 10 µL
Explanation:
A p1000 micropipet is set to dispense 1000 µL.
A p10 micropipet set to dispense 10 µL.
Based on the lesson how are individuals and economics similar
Answer:
HI!!
Explanation:
The correct answer is A) they both must decide how to allocate resources. Based on the lesson, individuals and economies are similar because both must decide how to allocate resources.
Answer:
A - They both must decide how to allocate resources
Explanation:
>.<
What is the density of an object with a mass of 83 g and a volume of 34 mL?
Type your answer with at least 2 decimal places.
Which rocky planet is the most similar to earth.Why?
Answer:
Mars
Explanation:
Mars is the planet with features that are really similar to the earth. As a matter of fact, Mars and the earth are referred to as "twin planets".
Mars and Earth are believed to have historically had even more similar attributes, however, that of mars was lost due to changes in the solar system.
The two planets are mostly similar because of their relatively similar size and proximity to the sun.
Write the structural and condensed formulas as well as the names for all isomers of C3H7Cl and C3H6Cl2.?
Answer:
[tex]C_3H_7Cl[/tex] = Two structures
[tex]C_3H_6Cl_2[/tex] = Four structures
Explanation:
We must remember that in an isomer we have the same molecular formula but different structures. Thus, for the molecule [tex]C_3H_7Cl[/tex] we can draw a linear structure of 3 carbons and change the position of the chlorine atom, obtaining two different structures.
For the molecule [tex]C_3H_6Cl_2[/tex], we can use similar logic. Place a chain of 3 carbons and change the position of the chlorine atoms in such a way that for this formula we will have 4 different structures.
See figures 1 and 2 for further explanations.
Fructose‑2,6‑bisphosphate is a regulator of both glycolysis and gluconeogenesis for the phosphofructokinase reaction of glycolysis and the fructose‑1,6‑bisphosphatase reaction of gluconeogenesis. In turn, the concentration of fructose‑2,6‑bisphosphate is regulated by many hormones, second messengers, and enzymes.
Answer:
Activate glycolysis/Inhibit gluconeogenesis: Increased levels of fructose-2,6-bisphosphate, activation of PFK-2
Activate gluconeogenesis/Inhibit glycolysis: Increased levels of glucagon, Increased levels of cAMP, Activation of fructose-2,6-bisphosphatase (FBPase-2)
Note: The question is incomplete. The complete question is given below and in the attachment.
Fructose‑2,6‑bisphosphate is a regulator of both glycolysis and gluconeogenesis for the phosphofructokinase reaction of glycolysis and the fructose‑1,6‑bisphosphatase reaction of gluconeogenesis. In turn, the concentration of fructose‑2,6‑bisphosphate is regulated by many hormones, second messengers, and enzymes. How do the following affect glycolysis and gluconeogenesis?
Explanation:
Fructose-2,6-bisphosphate is an allosteric effector for the enzymes phosphofructokinase-1 (PFK-1) and fructose-1,6-bisphosphatase (FBPase-1). It increases the affinity of PFK-1 for fructose-6-phosphate thereby activating glycolysis. However, it reduces the affinity of FBPase-1 for its substrate, fructose-1,6-bisphosphate thereby inhibiting gluconeogenesis.
Activation of phosphofructokinase-2 activates glycolysis and inhibits gluconeogenesis by catalyzing the phosphorylation of fructose-6-phosphate to form fructose-2,6-bisphosphate.
Increased levels of glucagon stimulates the synthesis of cAMpP which activates cAMP-dependent ptrotein kinase which phosphorylates the bifunctional enzyme PFK-2/FBPase-2. The phosphorylation of this enzyme inhibits its PFK-2 activity and activates its FBPase-2 activity. This results in the activation of gluconeogenesis and inhibition of glycolysis.
Fructose-2,6-bisphosphatase breaks down fructose-2,6-bisphosphate to fructose-6-phospshate and a phosphoryl group. This results in the activation of gluconeogenesis and the inhibition of glycolysis.
What energy transfer is occurring when a battery powered toy rolls across the floor ?
Iron(II) chloride is added to sodium carbonate. The reaction is described by the balanced equation below. (7 points) FeCl2(aq) + Na2CO3(aq) FeCO3(s) + 2NaCl(aq) i. Write the complete ionic equation from the balanced equation. (3 points) ii. What are the spectator ions in the reaction? (1 point) iii. Write the net ionic equation from the complete ionic equation. (2 points)
Answer:
Explanation:
FeCl₂(aq) + Na₂CO₃(aq) ⇒ FeCO₃(s) + 2NaCl(aq)
complete ionic equation
Fe⁺²(aq) + 2 Cl⁻(aq) + 2 Na⁺(aq) + CO₃⁻² (aq) ⇒ FeCO₃(s)+ 2 Na⁺(aq) +2Cl⁻(aq)
Spectator ions = Cl⁻(aq) , Na⁺(aq)
Net ionic equation
Fe⁺²(aq) + CO₃⁻² (aq) ⇒ FeCO₃(s).
The Complete ionic equation:
Fe²⁺(aq) + 2Cl⁻(aq) + 2Na⁺(aq) + CO₃²⁻(aq) → FeCO₃(s) + 2Na⁺(aq) + 2Cl⁻(aq)
ii. Spectator ions: Na⁺(aq) and Cl⁻(aq)
iii. Net ionic equation:
Fe²⁺(aq) + CO₃²⁻(aq) → FeCO₃(s)
An ionic equation is a chemical equation that shows the dissociation of all soluble ionic compounds into their respective ions in a solution. It represents the species present in their ionic form rather than as complete compounds.
In an ionic equation, only the ions involved in the chemical reaction are shown, while the spectator ions, which do not participate in the reaction, are omitted. This type of equation provides a more focused representation of the chemical reaction occurring between the ions.
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Could someone tell what element your
specific atom is based on your model?
Explain.
help! plz
Answer:
yes
Explanation:
the number of protons in the nucleus of an atom determines the type element: the number of protons in an element is the atomic number on the periodic table (number at the top)
Each atom has characteristic number of protons present in it's nucleus which is unique for that element.
What is an element?An element is defined as a substance which cannot be broken down further into any other substance. Each element is made up of its own type of atom. Due to this reason all elements are different from one another.
Elements can be classified as metals and non-metals. Metals are shiny and conduct electricity and are all solids at room temperature except mercury. Non-metals do not conduct electricity and are mostly gases at room temperature except carbon and sulfur.
The number of protons in the nucleus is the defining property of an element and is related to the atomic number.All atoms with same atomic number are atoms of same element.
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A student performed an experiment to test the acidity of foods. Put the following steps in the order they should occur.
The student
records the acidity of the food.
asks a question about food’s acidity.
observes that there are acidic foods.
presents the results to the class.
prepares to conduct the experiment.
creates a hypothesis about the acidity.
Answer:
prepare
creates
observe
ask
records
present
Witch two substances are needed for cellular respiration
Answer:
Oxygen and glucose
Explanation:
____________
How many milliliters of a 1M nitric acid solution are required to prepare 60mL of 6.7M solution?
A) 400 mL
B) 4mL
C) 0.25 mL
D) none of the above
Answer:
the number of milliliters of a 1M is 402mL
Explanation:
The computation of the number of milliliters could be determined by using the following formula
As we know that
[tex]V_1\times M_1 = V_2\times M_2[/tex]
where,
V_1 and V_2 are the starting and final volumes
And, the M_1 and M_2 are the starting and the final molarities
Now the V_1 is
[tex]V_1 \times 1M = 60mL \times 6.7M[/tex]
So, the V_1 is 402mL
Hence, the number of milliliters of a 1M is 402mL
What is the density of an object with a mass of 145.8g and an volume of 91.75 mL?
Answer:
Density = 1.6 g/mLExplanation:
Density of a substance can be found by using the formula
[tex]Density = \frac{mass}{volume} [/tex]
From the question
mass = 145.8 g
volume = 91.75 mL
Substitute the values into the above formula and solve for the Density
That's
[tex]Density = \frac{145.8}{91.75} [/tex]
= 1.5891
We have the final answer as
Density = 1.6 g/mL
Hope this helps you
What information about earthquakes do scientists gain from seismographs?
Answer:
how strong it is
Explanation:
Seismographs are not able to say when earthquake will happen, but they help humans to know how strong it is or if it is happening or not