Answer:
An unknown metal between 10-30 g is transferred to a test tube, place the tube in water that is boiling for ten minutes until it reaches a thermal equilibrium.
Explanation:
A glass of milk has a [H+]=1×10−6. What is the pH of this milk? Is this milk an acidic or a basic solution?
Answer:
DUDE YOUR ANSWER IS:
Explanation:
GIVEN BY YOU:
[H+]=(1*10^-6)
Taking negitive log on both sides we get,
-㏒[H+]=-㏒(1*10^-6)
now by power rule of exponent, and also we know that
-㏒[H+]=PH so we get
PH= -(-6)(log(10))
as we know log(10)=1 hence by putting we get
PH=6
acidic or a basic solution:
as PH<7 hence its acidic
if you like it pls comment and share it as well
so other get help of it
Predict whether the following reactions are spontaneous.
1. Pd(aq)2+H2g--------->Pd(s)+2H(aq+) Pd(aq2+) +2e- ----------> Pd(s)
E° 0.987 v
2. Sn(aq4+)+H2(g)--------->Sn(aq2+)+2H+ Sn(aq4+)+2e--------->Sn(aq)2+
E°0.154V
3. Ni(aq2+)+H2(g)--------->Ni(s)+2H(aq+) Ni(aq2+) +2e---------->Ni(s)
E° -0.250 V
4. Cd(aq2+)+H2(g--------> Cds)+2H(aq)+ Cd(aq)2 + +2e -------->
Cd(s) E°-0.403 v
From your answers, decide which of the above metals could be reduced by hydrogen
Answer:
1. spontaneous
2. spontaneous
3. Not Spontaneous
4. Not Spontaneous
Palladium and Sn^4+ can be reduced by hydrogen.
Explanation:
If we look at the electrochemical systems represented above, we will notice that in the first two cells, the metal should be reduced looking at the positive electrode potential of the process. This means that hydrogen can reduce the both metals. Electrons flow from the H2(g)/H^+(aq) half cell to the metal/metal ion half cell.
Similarly, when the standard electrode potential is negative, electrons flow from the metal/metal ion electrode to the hydrogen electrode.
Based on the reaction equations, a process is spontaneous if it gives a positive E°cell hence the answers above.
Monomer liquid and polymer powder nail enhancement are service
Answer:
Monomer liquid and polymer powder nail enhancement are lucrative service
Consider the two beakers labeled A and B. Beaker A contains 1 mole of iron atoms, and Beaker B contains 1 mole of lead atoms. Which statement concerning these samples is known with certainty?
The provided question is incomplete, however, the complete question is attached with answer:
Answer:
The correct answer is : option A. Beakers A and B contain an equal number of atoms.
Explanation:
No matter what is the element or substance, in one mole of any elemnet r metal or anything have 6.022×1023 everythings. So, beaker A have one mole of iron Fe and beaker B have one mole of Lead Pb, then the total atoms in each beaker will be equal that is :
1 mole of Fe = 1× 6.022×1023 atoms/mol
1 mole of Pb = 1× 6.022×1023 atoms/mol
Thus, the correct answer is: option A. Beakers A and B contain an equal number of atoms.
How much work does a gas do when it expands against a constant pressure of 0.600 atm from a volume of 50.00 mL to a volume of 440.00 mL?
Answer:
23.71J is the work that the gas do.
Explanation:
The work that a gas do under isobaric conditions follows the formula:
W = P*ΔV
Where W is work in atmL, P is the pressure and ΔV is final volume -Initial volume In Liters
Replacing with the values of the problem:
W = P*ΔV
W = 0.600atm*(0.44000L - 0.0500L)
W = 0.234atmL
In Joules (1atmL = 101.325J):
0.234atmL × (101.325J / 1 atmL) =
23.71J is the work that the gas do.
Which measurement is best supported in units of microliters ?
The mass of an atom of uranium
The volume of a water droplet in a cloud
The thickness of a strand of hair
The volume of the Atlantic Ocean
Answer:the volume of a water droplet in a cloud
Explanation:
Answer:
The volume of a water droplet in a cloud
Explanation:
just took the test
A rule or principle that has not changed over a period of hundreds of years, and it is usually
a concise statement, it is a
A) Theory
B) Scientific Law
C) Scientific statement
D) Conclusion
Acetyl chloride undergoes nucleophilic substitution at a faster rate than methyl acetate because:_________
A) the ester is more sterically hindered than the acid chloride.
B) the acid chloride is more sterically hindered than the ester.
C) the methoxide is a better leaving group than chloride.
D) esters hydrolyze faster than acid chlorides.
E) chloride is a better leaving group than methoxide.
Which of the following is a sign a chemical reaction has occurred?
Options
A) A blue liquid is mixed into a yellow liquid, and the mixture turns green.
B) A piece of metal is placed in water and produces sparks and gas.
C) A liquid is heated in a hot plate, and bubbles form.
D) A solid powder is mixed into a liquid and disappears
Answer:
A piece of metal is placed in water and produces sparks and gas.
The sign of a chemical reaction has occurred is a piece of metal is placed in water and produces sparks and gas. The correct option is B.
What is a chemical reaction?Chemical changes, often known as chemical reactions, are the transformation of one or more compounds into one or more brand-new, separate substances. In other words, a chemical change is a process based on atomic rearrangement.
Metal is malleable and luster substance. They are gold, silver, magnesium, etc. They are present in the periodic table. Furthermore, they are highly reactive and soft.
A chemical reaction is happening in the reaction of water when it produces a spark or gas when reacting with another substance.
Thus, the correct option is B. A piece of metal is placed in water and produces sparks and gas.
To learn more about chemical reactions, refer to the link:
https://brainly.com/question/14929452
#SPJ2
Identify the options below that can be determined from a nuclide symbol.
A. The charge of the nuclide
B. The atomic number of the nuclide
C. The number of protons in the nuclide
D. The number of isotopes of that element
Answer:
A. The charge of the nuclide
B. The atomic number of the nuclide
C. The number of protons in the nuclide
Explanation:
The general nuclide symbol is in the picture.
Where X is the element you want to represent, A the mass number (That is mass of protons + mass of neutrons), Z is atomic number (Number of protons), and C is the charge of the nuclide.
Thus, you can determine from the nuclide symbol:
A. The charge of the nuclide . YES. Is C.
B. The atomic number of the nuclide . YES. Is Z.
C. The number of protons in the nuclide . YES. From the difference of A - Z.
D. The number of isotopes of that element. NO. It is not possible to determine number of isotopes of an element from a nuclide symbol.
odor extensive or intensive
Answer:
Odour is intensive
Explanation:
intensive properties are Independent of the amount of matter
As a gas changes to a solid does it lose energy or gain energy?
Answer:
It loses thermal energy and the movement of particles decreases.
Explanation:
The process of a gas turning to a solid is called condensation.
Calculate the mass percent of HOCH 2CH 2OH in a solution made by dissolving 3.2 g of HOCH 2CH 2OH in 43.5g of water.
Answer:
[tex]\%m/m=6.85\%[/tex]
Explanation:
Hello,
In this case, we are asked to compute the by mass percent for the given 3.2 g of ethylene glycol in 43.5 g of water. In such a way, since the by mass percent is computed as follows:
[tex]\%m/m=\frac{m_{solute}}{m_{solute}+m_{solvent}} *100\%[/tex]
Whereas the solute is the ethylene glycol and the solvent the water, therefore we obtain:
[tex]\%m/m=\frac{3.2g}{3.2g+43.5g} *100\%\\\\\%m/m=6.85\%[/tex]
Best regards.
Carry out the following calculation, paying special attention to the significant figures (where 4/3 is exact), rounding, and units. 
3.39x10^7 g/(4/3)(3.1416)(1.65x10^2 cm)^3=____g/cm^3
Answer:
Value = 1.80 g/cm³ (Approx)
Explanation:
Given:
[tex]\frac{3.39 \times 10^7g}{(\frac{4}{3} )(3.1416)(1.65 \times 10^2 cm)^3}[/tex]
Computation:
[tex]\frac{3.39 \times 10^7g}{(\frac{4}{3} )(3.1416)(1.65 \times 10^2 cm)^3} \\\\\frac{3.39 \times 10^7g}{(\frac{4}{3} )(3.1416)(4.492125 \times 10^6 cm^3)} \\\\ \frac{3.39 \times 10^7g}{(\frac{4}{3} )(3.1416)(4.492125 \times 10^6 cm^3)}\\\\ \frac{3.39 \times 10^7g}{18.8166132\times 10^6 cm^3} \\\\ 1.80159945g/cm^3[/tex]
Value = 1.80 g/cm³ (Approx)
The density has been calculated by computing the equation as [tex]\rm 1.802\;g/cm^3[/tex].
The calculation has been performed for density, as it has been performed for mass per unit volume.
The calculations can be performed as:
[tex]\rm \implies \dfrac{3.39\;\times\;10^7\;g}{\frac{4}{3}\;\times\;(3.1416)\;(1.65\;\times\;10^2)^3\;cm^3 } \\\implies \dfrac{3.39\;\times\;10^7\;g}{\frac{4}{3}\;\times\;(3.1416)\;(4.49\;\times\;10^6)\;cm^3 }\\\implies \dfrac{3.39\;\times\;10^7\;g}{\frac{4}{3}\;\times\;14.1124\;\times\;10^6\;cm^3 }\\[/tex]
The equation has been further simplified for density as:
[tex]\rm \implies \dfrac{3.39\;\times\;10^7\;g}{18.811\;\times\;10^6\;cm^3 } \\\implies 1.802\;g/cm^3[/tex]
The density has been calculated by computing the equation as [tex]\rm 1.802\;g/cm^3[/tex].
For more information about rounding units, refer to the link:
https://brainly.com/question/3808339
Boron is an exception to the octet rule and can take up to 10 electrons in its valence shell.
True
False
Answer:
False
Explanation:
Boron is an exception to the octet rule because it possesses less than eight electrons. Boron has five electrons with three of them being valence electrons and therefore has an incomplete octet. It readily forms compounds in which it has six valence electrons, rather than the usual eight.
Hope that helps.
Considering the exception to the octet rule, the statement is false because Boron is an exception to the octet rule and can take up to 6 electrons in its valence shell.
An exception to the octet rule is when there are too few valence electrons resulting in an incomplete octet. That is, the default exceptions imply that there can be covalently bonded atoms that surround themselves with fewer than eight electrons.
This exception occurs with boron. Boron has an incomplete octet because it only has six electrons around it. That is, boron has three valence electrons and can only form electron pair bonds in two locations, gaining stability only with 6 valence electrons.
In summary, the statement is false because Boron is an exception to the octet rule and can take up to 6 electrons in its valence shell.
Learn more:
https://brainly.com/question/21922467?referrer=searchResultshttps://brainly.com/question/12089726?referrer=searchResultshttps://brainly.com/question/20347349?referrer=searchResultsa sample of what looks like silver has a mass of 1.7 kg and a volume of 0.164 liters is it really silver
Answer:
It is not 100% silver, but it contains a high percentage (more than the 98% for sure) of silver.
Explanation:
Hello,
In this case, since the density of silver is 10.49 g/cm³, we can substantiate if the given sample is silver by computing is density as shown below:
[tex]\rho =\frac{m}{V}=\frac{1.7kg}{0.164L}*\frac{1000g}{1kg} *\frac{1L}{1000cm^3}\\ \\\rho=10.37g/cm^3[/tex]
In such a way, since we find a slight difference in the computed density, we can say it is not 100% silver, but it contains a high percentage (more than the 98% for sure) of silver.
Regards.
Balance equation for Magnesium + Sulphuric acid = Magnesium sulphate + Hydrogen gas
Explanation:
Hey, there!!
Your question is,
Magnesium + sulphuric acid = magnesium + hydrogen gas.
I.e.
[tex]mg + h2so4 = mgso4 + h2 \: [/tex]( hydrogen gas)
Here,
reactant and product have equal atoms.
so, it is alreday balanced.
They all are equal and alredy balanced.
Hope it helps...
Answer:
Mg + H2SO4 → MgSO4 + H2
Explanation:
The chemical equation shows magnesium (Mg) and sulfuric acid (H2SO4) on one side and magnesium sulfate (MgSO4) and hydrogen gas (H2) on the other.
Mg + H2SO4 → MgSO4 + H2
In the measurement 0.502 L, which digit is the estimated digit? A. 5 B. 3 C. The 0 to the left of the decimal point D. The 0 immediately to the left of the 3
Answer:
no c
Explanation:
what is the color of dilute hydrochloric acid when we use the universal indicator ? only given that it is corrosive
Answer:
dark red
Explanation:
because dilute hcl is acid
dark red is the correct answer.
Dinitrogen tetroxide and hydrazine (N2H4) undergo a redox reaction in which nitrogen and water are formed as products. What mass of nitrogen could be produced when 50.0 g of dinitrogen tetroxide and 45.0 g of hydrazine are combined?
Answer:
The mass of nitrogen molecule [tex]N_2[/tex] = 45.65 g
Explanation:
The equation for the redox reaction can be represented as follows:
[tex]\mathtt{2N_2H_4 +N_2O_4 \ \to \ 3N_2 + 4H_2O}[/tex]
We know that:
numbers of moles = mass/molar mass
For [tex]\mathtt{N_2O_4}[/tex] :
number of moles = 50g/92 g/mol
number of moles = 0.5435 mol
For [tex]\mathtt{N_2H_4}[/tex] :
number of moles = 45 g/ 32 g/mol
number of moles = 1.40625 mol
From the above equation;
number of moles of [tex]\mathtt{N_2O_4}[/tex] needed = 1/2 moles of [tex]\mathtt{N_2H_4}[/tex] = 1/2 × 1.40625 mol
= 0.703125 mol
The amount of [tex]\mathtt{N_2O_4}[/tex] present = 0.5435 moles which is less than the needed. As such [tex]\mathtt{N_2O_4}[/tex] is the limiting reagent
The number of moles of nitrogen molecule [tex]N_2[/tex] produced = 3 × ([tex]\mathtt{N_2O_4}[/tex])
= 3 × 0.5435
= 1.6305 mol
The mass of nitrogen molecule [tex]N_2[/tex] = number of moles of [tex]N_2[/tex] × molar mass of [tex]N_2[/tex]
The mass of nitrogen molecule [tex]N_2[/tex] = 1.6305 mol × 28 g/mol
The mass of nitrogen molecule [tex]N_2[/tex] = 45.654 g
The mass of nitrogen molecule [tex]N_2[/tex] = 45.65 g
Determine the pH of the resulting solution if 25 mL of 0.400 M strychnine (C21H22N2O2) is added to 50 mL of 0.200 M HCl? Assume that the volumes of the solutions are additive. For strychnine at the temperature of the experiment, Kb = 1.8 × 10-6.
Answer:
pH = 4.56
Explanation:
The strychnine reacts with HCl as follows:
C₂₁H₂₂N₂O₂ + HCl ⇄ C₂₁H₂₂N₂O₂H⁺ + Cl⁻
For strychnine buffer:
pOH = 5.74 + log [C₂₁H₂₂N₂O₂H⁺] / [C₂₁H₂₂N₂O₂]
Initial moles of C₂₁H₂₂N₂O₂ are:
0.025L * (0.400 mol / L) = 0.01 moles C₂₁H₂₂N₂O₂
And of HCl are:
0.05L * (0.200 mol / L) = 0.01 moles HCl
That means after the reaction, you will have just 0.01 moles of C₂₁H₂₂N₂O₂H⁺ in 50mL + 25mL = 0.075L. And molarity is:
[C₂₁H₂₂N₂O₂H⁺] = 0.01 mol / 0.075L = 0.1333M
This conjugate acid, is in equilibrium with water as follows:
C₂₁H₂₂N₂O₂H⁺(aq) + H₂O(l) ⇄ C₂₁H₂₂N₂O₂ + H₃O⁺
Where Ka = Kw / Kb = 1x10⁻¹⁴ / 1.8x10⁻⁶ = 5.556x10⁻⁹
Ka is defined as:
Ka = 5.556x10⁻⁹ = [C₂₁H₂₂N₂O₂] [H₃O⁺] / [C₂₁H₂₂N₂O₂H⁺]
In equilibrium, concentrations are:
C₂₁H₂₂N₂O₂ = X
H₃O⁺ = X
C₂₁H₂₂N₂O₂H⁺ = 0.1333M - X
Replacing in Ka expression:
5.556x10⁻⁹ = [X] [X] / [0.1333M - X]
7.39x10⁻¹⁰ - 5.556x10⁻⁹X = X²
7.39x10⁻¹⁰ - 5.556x10⁻⁹X - X² = 0
Solving for X:
X = - 2.72x10⁻⁵M → False solution. There is no negative concentrations
X = 2.72x10⁻⁵M → Right solution.
As H₃O⁺ = X
H₃O⁺ = 2.72x10⁻⁵M
And pH = -log H₃O⁺
pH = 4.56Which of the following is included in nuclide symbols, but is not strictly necessary for the identification of the nuclide?
a. mass number
b. atomic number
c. isotope number
d. none of the above
Answer:
c. isotope number
Explanation:
Mass Number is the sum total of mass of protons and neutrons present in the nucleus of an atom. Generally they are being used in distinguishing isotopes. E.g Carbon - 12, Carbon - 13
Atomic Number is the number of protons. Every single element has it's unique atomic number and can be used in identification purpose. E.g Carbon - 6, Hydrogen - 1.
The correct option is option C. This is the symbol that is not necessary for the identification of a nuclide.
Answer: B, atomic number
10.
17.0cm
23.0cm
4,00cm
A 38.6 kg marble slab is shown above. What is its density? Give your
answer to the nearest tenth.
g/cm3
Enter the answer
Check it
Answer:
Density, [tex]\rho=24.68\ g/cm^3[/tex]
Explanation:
Mass of a marble slab is 38.6 kg 38600 grams
The dimensions of the marble is 17 cm×23 cm×4 cm
We need to find its density. Mass per unit volume equals density. So,
[tex]\rho=\dfrac{m}{V}\\\\\rho=\dfrac{m}{lbh}\\\\\rho=\dfrac{38600\ g}{(17\times 23\times 4)\ cm^3}\\\\\rho=24.68\ g/cm^3[/tex]
So, the density of the marble slab is [tex]24.68\ g/cm^3[/tex]
Which unit is not a measurement of volume?
cm
L
ml
Cm^3
Which of the following hypotheses is testable by using the scientific method?
a) all man are mortal
b) the best color is blue
c) no life exists on other planets
d) all swans are white
e) swimming if fun
Answer:
d
Explanation:
The only hypothesis that is testable using the scientific method would be that all swans are white.
The scientific method involves a series of steps through which scientists are able to arrive at a conclusion about the natural world. The steps include observation, drawing up falsifiable hypotheses from observations, testing the hypotheses using experiments, and then arriving at conclusions based on the data gathered from the experiment.
There is no way to test the mortality of all men as this will require harming humans in order to prove their mortality. The best color is also subjective as individuals have their preference when it comes to color. There is no way to prove the hypothesis that no life exists on other planets as this will require visiting other planets, a gesture that is practically impossible. That swimming is fun can also be subjective. Not everyone finds swimming interesting.
The hypothesis that all swans are white can be tested by sampling the population of swans in different areas and recording their colors objectively.
Hence, the correct option is d.
The hypothesis 'all swans are white' is testable by using the scientific method (Option d).
The scientific method is a series of sequential steps by which it is possible to find an explanation to scientific questions.The hypotheses are plausible explanations used by scientists to answer questions on the natural world.A hypothesis must be testable which means it is positive to make observations that agree or disagree with such explanation.In conclusion, the hypothesis 'all swans are white' is testable by using the scientific method (Option d).
Learn more in:
https://brainly.com/question/2695653
The liquid 2-chloro-2,3-dimethylbutane has a density of 0.878 g/mL at 20.0°C. If a 138 gram sample of this compound is needed, what volume of the liquid at 20.0°C must be provided? volume= mL
Answer:
157.2 mL
Explanation:
The following data were obtained from the question:
Density (D) of liquid = 0.878 g/mL
Mass (m) of liquid = 138 g
Volume (V) of liquid =.?
Density of a substance is simply defined as the mass of the substance per unit volume of the substance. Mathematically, it is expressed as:
Density (D) = mass /volume
D = m/V
With the above formula, we can obtain the volume of the liquid as follow:
Density (D) of liquid = 0.878 g/mL
Mass (m) of liquid = 138 g
Volume (V) of liquid =.?
D = m/V
0.878 = 138/V
Cross multiply
0.878 × V = 138
Divide both side by 0.878
V = 138/0.878
V = 157.2 mL
Therefore, 157.2 mL of the liquid must be provided.
How many grammes of alkali are present in 150 cm ^(3) of 3 mol/dm^(3) of sodium hydroxide
Answer:I’m here for points
Explanation:yeah cuz
Predict the reactivity of silicon in water relative to that of sodium, magnesium, and aluminium. Explain your answer. How does the reactivity of the halogens vary within its own group from top to bottom?
Answer:
See explanation
Explanation:
The reactivity of metals has a lot to do with their position in the electrochemical series. However, it is also known that metallic character decreases across the period. This implies that as we move from left to right along the periodic table. Sodium, magnesium, aluminum and silicon continues to decrease in metallic character. As a matter of fact, silicon is a metalloid and not a pure metal.
Sodium reacts with cold water to give a vigorous reaction,magnesium and aluminium reacts with steam at red heat.
Silicon does not react with water, even as steam, under normal conditions.
Reactivity can be given as the ability of the atom to lose or gain electrons. The reactivity can be silicon is least as compared to sodium and other metals in water.
What is the trend of reactivity in the periodic table?The periodic table has the arrangement of the elements in groups and periods in the table.
On moving from left to right in the periodic table, the number of electrons in the same shell increase, thereby making the loss of electrons difficult. Thus, on moving from left to right in the periodic table, the metal reactivity decreases.
Hence, silicon present in the right most of the periodic table has the lower reactivity as compared to the sodium, magnesium, and aluminum on the left side of the periodic table.
In the periodic table, on moving from top to bottom, the number of shells increases, decreasing the force of attraction to the outermost electron. Thus, the metal reactivity increases down the group.
Learn more about reactivity, here:
https://brainly.com/question/1598581
what type of equation is MgSO4 (aq) + Na2CO3 (aq) → MgCO3 (s) + Na2SO4 (aq)
You are comparing a reaction that produces a chemical change and one that produces a physical change. What evidence could you use to determine which type of change is occurring? \
Answer:
You are comparing a reaction that produces a chemical change and one that produces a physical change. What evidence could you use to determine which type of change is occurring?
If the reaction is a chemical change, new substances with different properties and identities are formed. This may be indicated by the production of an odor, a change in color or energy, or the formation of a solid.
Sample Response: If the reaction is a chemical change, new substances with different properties and identities are formed. This may be indicated by the production of an odor, a change in color or energy, or the formation of a solid.
What did you discuss in your response? Check all that apply.
the production of an odor
a change in energy
a change in color
the formation of a solid
the formation of new substances
a change in properties and identities
A chemical change may result in the following;
Evolution of gasChange in temperature of the reaction mixtureAppearance of a solidChange in colorA Physical change may result in the following;
Change in appearanceChange in sizeChange in shapeChange in textureA chemical change leads to the formation of a new substance. This implies that the composition of the substance has being changed.
A physical change does not lead to a change in the nature of the substance. However, the appearance, shape, texture or size of the substance may change.
Learn more: https://brainly.com/question/6284546