Answer:
Yes
Explanation:
It was Dmitri Mendeleev, a Russian chemist and teacher.
Answer:
No, it wasn't. On Feb.17 in 1869, a very intelligent Russian professor of chemistry, Dimitri Ivanovich Mendeleev created his first part of the periodic table. I hope that helps you.
Explanation:
An object accelerates 12.0 m/s2 when a force of 6.0 newtons is applied to it. What is the mass of the object?
Answer:
The mass of object is 0.5 Kg.
Explanation:
Given data:
Acceleration of object = 12.0 m/s²
Force on object = 6.0 N
Mass of object = ?
Solution:
Formula:
F = m×a
F = force
m = mass
a = acceleration
Now we will put the values in formula.
6.0 N = m × 12.0 m/s²
m = 6.0 N / 12.0 m/s²
( N = kg.m/s²)
m = 0.5 kg
The mass of object is 0.5 Kg.
A 4.534 g sample of a solid mixture was analyzed for barium ion. First the rock was crushed in a mortar and pestle. 100% of the sample was transferred to a beaker, where it was dissolved in 150.0 mL of d.i. water. to give 152 mL of solution. The aqueous sample was then analyzed by adding a small excess of sulfuric acid. The resultant reaction produced a precipitate of barium sulfate, which was collected by filtration, rinsed, dried and weighed. If 0.5376 g of barium sulfate was obtained, what was the mass percent of barium in the original sample? What was the molar concentration barium in the 152 mL of solution prior to adding sulfuric acid? Show work clearly; include a balanced net ionic chemical equation, units and sig. figs.
Answer:
6.976%
0.0152 M
Explanation:
Step 1: Write the balanced chemical equation
Ba²⁺(aq) + H₂SO₄(aq) ⇒ BaSO₄(s) + 2 H⁺(aq)
The balanced net ionic chemical equation is:
Ba²⁺(aq) + SO₄²⁻(aq) ⇒ BaSO₄(s)
Step 2: Calculate the moles corresponding to 0.5376 g of BaSO₄
The molar mass of BaSO₄ is 233.39 g/mol.
0.5376 g × (1 mol/233.39 g) = 2.303 × 10⁻³ mol
Step 3: Calculate the moles of Ba²⁺ that produced 2.303 × 10⁻³ moles of BaSO₄
The molar ratio of Ba²⁺ to BaSO₄ is 1:1. The moles of Ba²⁺ are 1/1 × 2.303 × 10⁻³ mol = 2.303 × 10⁻³ mol.
Step 4: Calculate the mass corresponding to 2.303 × 10⁻³ moles of Ba²⁺
The molar mass of Ba²⁺ is 137.33 g/mol.
2.303 × 10⁻³ mol × 137.33 g/mol = 0.3163 g
Step 5: Calculate the mass percent of barium in the original sample
0.3163 g of barium ion were in a 4.534 g-sample. The mass percent of barium ion is:
0.3163 g/4.534 g × 100% = 6.976%
Step 6: Calculate the molar concentration barium in the 152 mL of solution
2.303 × 10⁻³ moles of barium ion were in 152 mL (0.152 L) of solution. The molarity of barium ion is:
M = 2.303 × 10⁻³ mol/0.152 L = 0.0152 M
Why is digestion an example of both physical and chemical change simultaneously
Answer: Here is why,
Explanation: Burning of wood is a example of both physical and chemical change. ... Another example is digestion of food ,first the food is chewed into small pieces this is a chemical change while in the actual digestion process it is chemically broken with the help of digestive enzymes and saliva
A beaker contains 42.0 mL of carbon tetrachloride ( CCl4 , density is 1.59 g/mL). Determine how many molecules of carbon tetrachloride are in the beaker.
Answer:
Number of molecules = 2.61 x 10²³
Explanation:
Given:
Volume of tetra-chloride = 42 ml
Density = 1.59 g/ml
Find:
Number of molecules
Computation:
Mass = Volume of tetra-chloride x Density
Mass = 42 x 1.59
Mass = 66.78
Molecular mass of tetra-chloride = 154 g/mol
Moles = 66.78 / 154
Moles = 0.4337
0.4337 mole = 0.4337 x Avogadro number
0.4337 mole = 0.4337 x 6.022 x 10²³
Number of molecules = 2.61 x 10²³
 what is 19.8-17.1
Answer: it should be 2.8
Explanation:
30 g of pineapple added to a drink the drink rises 5 ml what is the density of the pineapple
Answer:
Density of pineapple is 6 g/mL.
Explanation:
Given data:
Mass of pineapple = 30 g
Volume rises = 5 mL
Density of pineapple = ?
Solution:
Density:
Density is equal to the mass of substance divided by its volume.
The symbol used for density is called rho. It is represented by ρ. However letter D can also be used to represent the density.
Units:
SI unit of density is Kg/m3.
Other units are given below,
g/cm3, g/mL , kg/L
Formula:
D=m/v
D= density
m=mass
V=volume
The volume rises by drink is actually the volume of pineapple.
d = 30 g/ 5 mL
d = 6 g/mL
Density of pineapple is 6 g/mL.
Which field is not a branch of biology
Botany
Geology
Zoology
Genetics
Answer:
Geology
Explanation:
Geology is not a branch of biology.
Biology is the study of all forms of lives. Bio - life and logy - study
It consists of studies of plants, animals and micro-organisms. Some of its sub-branches are zoology, botany, genetics, micro-biology e.t.c.
Geology is the study of the earth. It deals with the materials that makes up the earth and how they have evolved through time. some of its sub-disciplines are hydro-geology, stratigraphy, geochemistry e.t.cAnswer:
geology
Explanation: I took the test.
Which characteristics describe the genetic code of humans? Select three options
Answer:
1. Can help in development of effective medications
2. Can help explain genetic diseases
3. Composed of about 19,000 genes
Explanation:
The other answer options are misleading.
Genetic code of humans can help with understanding more than just human genetics.
Human genetics is composed of 23 chromosome pairs, for a total of 46 chromosomes.
(b) in the direct hydration method, ethene reacts with steam. The equation for this reaction is C2H4 + H2O = C2H5OH
State the temperature and pressure used in this reaction.
Answer:
20 degree and 4000000N
what is extraction .....???
Answer:
Extraction is the action of removing something.
Explanation:
Do all variations help organisms survive
Answer:
Yes
Explanation:
Or maybe i dont really know what it mean
Calculate the number of hydrogen atoms in 41.4 g of
ethyl alcohol, C2H60.
Answer:
3.25 x 10²⁴ atoms of H
Explanation:
First you have to convert from grams to moles of C₂H₆O using the molar mass of C₂H₆O, which is 46.06 g/mol. Then convert from moles of C₂H₆O to moles of H using the ratio within the compound; for every molecule of C₂H₆O, there are 6 H atoms. Then lastly, because moles just represent a number in the same way a dozen does, we convert from moles of H to the number of atoms of H. 1 mole H = 6.022 x 10²³ atoms of H.
[tex]41.4g*\frac{1molC2H6O}{46.06C2H6O} * \frac{6 mol H}{1molC2H6O} * \frac{6.022 * 10^2^3atomsH}{1molH} = 3.2476 x 10^2^4atomsH[/tex]
Round to lowest number of significant figure which is three to get 3.25 x 10²⁴.
To see the number of atoms of an element in a given molecule we need to multiply stoichiometry to the number that is written on the foot of the element that is stoichiometry. The the total number of atoms of hydrogen atoms in 41.4 g of ethyl alcohol, C₂H₆0 is 5.35×10²³ atoms.
What is atom?Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided. Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit.
Number of atoms =number of moles×6.022×10²³ (Avogadro number)
number of moles= given mass÷ Molar mass
Given mass=41.4 g
Molar mass of C₂H₆0=46.07 g/mol
number of moles= 41.4 g ÷ 46.07 g/mol=0.89mol
Number of atoms =0.89mol×6.022×10²³ (Avogadro number)
=5.35×10²³ atoms
Therefore, the total number of atoms of hydrogen atoms in 41.4 g of
ethyl alcohol, C₂H₆0 is 5.35×10²³ atoms.
To know more about atom, here:
https://brainly.com/question/13518322
#SPJ2
I have a question. Does anyone have a crush on their classmates? I do!
Answer:
I never had a crush on anyone
Explanation:
You have 100. grams of potassium bromide (KBr). How many moles do you have? (1 mole KBr = 119 g KBr)
0.840 mole KBr
1.00 mole KBr
1.19 mole KBr
2.00 mole KBr
Answer:
0.840
Explanation:
The 100 grams of KBr have been equivalent to 0.84 moles. Thus, option A is correct.
The moles can be defined as the mass of the compound with respect to the molecular mass. The moles can be given as:
Moles = [tex]\rm \dfrac{weight}{Molecular\;weight}[/tex]
The molecular weight has been the mass of the constituents of the atoms present in the compound.
The compound KBr has a molecular mass of 119 g/mol.
The given mass of the compound has been 100 grams.
The moles of KBr can be given as:
Moles of KBr = [tex]\rm \dfrac{100}{119}[/tex]
Moles of KBr = 0.84 moles.
The 100 grams of KBr have been equivalent to 0.84 moles. Thus, option A is correct.
For more information about the moles, refer to the link:
https://brainly.com/question/2437143
What is the frequency of a photon with an energy
Answer:
option b is correct option = (6.76×10¹⁴ Hz)
Explanation:
Given data:
Wavelength of photon = 4.42×10⁻⁷ m
Speed of light = 2.99×10⁸ m/s
Frequency of radiation = ?
Solution:
Formula:
Speed of wave = frequency × wavelength
Now we will rearrange this formula.
frequency = Speed of wave / wavelength
f = c/ λ
f = 2.99×10⁸ m/s / 4.42×10⁻⁷ m
f = 0.676×10¹⁵ Hz (s⁻¹ = Hz)
f = 6.76×10¹⁴ Hz
Thus option b is correct option.
which statement is true about the atomic masses?
A: it is never greater than the atomic number.
B: it can be greater than the atomic number.
C: it always equals the atomic.
D: it is always lower than the atomic number.
it is never greater than the atomic number.
OR,
Atomic mass is greater than Atomic number.. so, Answer is A . If you like this answer then mark this answer as BRAINLIEST answer.Thank you ☺️☺️
The difference between the two types of succession !!!??!?
Answer:
Hope it help you
Stayhomestaysafe
Plz mark my answer brainliest✍️✍️
Explanation:
Primary succession is the series of community changes which occur on an entirely new habitat which has never been colonized before. For example, a newly quarried rock face or sand dunes. Secondary succession is the series of community changes which take place on a previously colonized, but disturbed or damaged habitat.
REAL NAME - SHRESTH DUBEY
Which of the following cannot be read directly from the periodic table?
an element's atomic mass
an element's number of neutrons
an element's symbol
an element's number of protons
PLEASE HELPPP!!!!!!!!
Explanation:
Label A: oceanic - oceanic
Label B: oceanic - continental
Label C: continental - continental
Answer:
Oceanic-continental convergence---- letter B.
Oceanic-oceanic convergence ---- letter A.
Continental-continental convergence ---- letter C
plz mark brainliest
the pH of a HClO4 solution was measured as 4.251. What would be the concentration of HClO4 in this solution
Answer:
[tex]0.000056[/tex]
Explanation:
If [tex]pH[/tex] is given then hydronium ion concentration is equal to [tex]-log[H_3O^+][/tex]
The hydronium ion concentration can be found from the pH using the following formula:
Hydronium ion concentration = [tex]10^{-pH}[/tex]
As the pH of a HClO4 solution was measured as 4.251,
put [tex]pH=4.251[/tex]
So,
Concentration of HClO4 in the solution = [tex]10^{-4.251}=0.000056[/tex]
True or false, the nucleus is the core of an atom
Answer:true
Explanation:
The neutrons and the protons are what stay there
How many total atoms are in one molecule of maltose?
Answer:
The total number of atoms is 12 + 22 + 11 = 45, so carbon atoms are 12/45 of the total.
Explanation:
Determine the milliliters of paint in a 5.0 gallon bucket
Ans: 18950 ML
Answer:
the answer is 18,927,06.
Explanation:
I just took the test ; )
A chemist dissolves 320.mg of pure nitric acid in enough water to make up 290.mL of solution. Calculate the pH of the solution. Be sure your answer has the correct number of significant digits.
Answer:
1.7
Explanation:
The formula to be used here is;
pH = -log[H⁺]
To determine the concentration of H⁺ of the nitric acid (HNO₃), formula for molarity is used
Molarity = number of moles/volume (in dm³ or L)
number of moles (n) = given mass/molar mass
Molar mass of HNO₃ = 1 + 14 + (16 x 3)
= 63g
given mass (in grams) = 320mg⇔0.32g (where 1000mg = 1g)
Thus; n = 0.32/63
n = 0.0051 moles
Volume of acid = 290 mL ⇔ 0.29 L (where 1000 mL = 1L)
Molarity = n/volume;
0.0051/0.29
Molarity = 0.018M
pH = -log 0.018
pH = 1.7
Which type of investigation is based on observation?
Answer:
Quantitative Observations
Explanation:
How can you use the periodic table to predict reactivity?
Giving Brainliest!!!
Answer:
hi
Explanation:
how r u today
What is inside a Atom?
Answer:
there are three different subatomic particles inside them: the protons, neutrons, and electrons
What do you notice about the relationship between the force strength and the size of the velocity change?
Answer:
fkv SFHHHHHHHHHCB FSSSSZCHJjjjb .SFFHHHHHHHHC
Explanation:
What do you notice about the relationship between the force strength and the size of the velocity change?
Uuuuuuu
What will happen when the valve between a 2.00-L bulb, in which the gas pressure is 2.00 atm, and a 3.00-L bulb, in which the gas pressure is 4.50 atm, is opened? Assume the temperature remains constant. (For this question, label each statement as True or False and give an explanation/justification for each of your answers to receive credit. No credit is given for only True or False answers with no adequate justification. To receive credit you must provide justification. You may have to give numerical answers followed by verbal explanations. You can use any reasoning that you see fit but be as thorough as possible.)
The two gases will mix and react.
The two gases will remain separate and will not mix.
The two gases will occupy a volume of 5.0 L and the final pressure in the two bulbs will be 6.50 atm.
The two gases will occupy a volume of 5.0 L and the final pressure in the two bulbs will be 3.50 atm.
The two gases will occupy a volume of 5.0 L and the final pressure in the two bulbs will be 3.25 atm.
Answer:
- The two gases will mix and react.: FALSE.
- The two gases will remain separate and will not mix: FALSE.
- The two gases will occupy a volume of 5.0 L and the final pressure in the -two bulbs will be 6.50 atm.: FALSE.
- The two gases will occupy a volume of 5.0 L and the final pressure in the two bulbs will be 3.50 atm.: TRUE.
- The two gases will occupy a volume of 5.0 L and the final pressure in the two bulbs will be 3.25 atm: FALSE.
Explanation:
Hello.
In this case, given the options, since the total volume of the container includes the both of them, we find that:
- The two gases will mix and react: FALSE, since we do not know the identity of the gases which could be the same or two different inert gases.
- The two gases will remain separate and will not mix: FALSE, since as the valve is opened, the total gas will occupy the entire volume as the volume of a gas is the same to the container based on its constant molecules movements.
- The two gases will occupy a volume of 5.0 L and the final pressure in the two bulbs will be 6.50 atm: FALSE, since in this case, by using the Boyle's law for the first compartment we obtain the pressure of the gas there:
[tex]P_2V_2=P_1V_1\\\\P_2=\frac{P_1V_1}{V_2} =\frac{2.00atm*2.00L}{5.00L} =0.8atm[/tex]
Now, we reuse it for the gas at the 3.00-L bulb to find its final pressure:
[tex]P_2V_2=P_1V_1\\\\P_2=\frac{P_1V_1}{V_2} =\frac{2.00atm*3.00L}{5.00L} =2.7atm[/tex]
So the final pressure is:
[tex]P_{TOTAL}=0.8atm+2.7atm\\\\P_{TOTAL}=3.5atm[/tex]
- The two gases will occupy a volume of 5.0 L and the final pressure in the two bulbs will be 3.50 atm: TRUE considering the total pressure computed above.
- The two gases will occupy a volume of 5.0 L and the final pressure in the two bulbs will be 3.25 atm: FALSE since the final pressure is 3.5 atm.
Regards.
3) A certain reaction has the following general form: A + B à AB At a particular temperature the concentration versus time were collected for this reaction, and a plot of ln[A]t versus time resulted in a straight line with a slope of −3.7 x 10−3 s−1. Show your math! (5 points) a. What is the order of the reaction? b. What is the rate constant (including units)? c. Calculate the half-life for the reaction. d. If the initial concentration of A is 0.250 M, what is the concentration after 220 seconds?
Answer:
a. First order.
b. [tex]k=3.7x10^{-3}s ^{-1}[/tex]
c. [tex]t_{1/2}=187.3s[/tex]
d. [tex][A]=0.111M[/tex]
Explanation:
Hello.
a. In this case since the slope is in s⁻¹ we can infer that the lineal form of the rate law is:
[tex]ln[A]=-kt+ln[A]_0[/tex]
Which is also:
[tex]y=mx+b[/tex]
It means that the reaction is first-order as slope equals the negative of the rate constant which also has units of first-oder reaction.
b. Since the slope is −3.7 x 10−3 s−1 the rate constant is:
[tex]k=-m\\\\k=-(-3.7x10^{-3}s ^{-1})\\\\k=3.7x10^{-3}s ^{-1}[/tex]
c. For first-order reactions, the half-life is:
[tex]t_{1/2}=\frac{ln(2)}{k}\\ \\t_{1/2}=\frac{ln(2)}{3.7x10^{-3}s^{-1}}\\\\t_{1/2}=187.3s[/tex]
d. In this case, since the integrated first-order rate law is:
[tex][A]=[A]_0exp(-kt)[/tex]
The concentration once 220 seconds have passed is:
[tex][A]=0.250Mexp(-3.7x10^{-3}s^{-1}*220s)\\\\[/tex]
[tex][A]=0.111M[/tex]
Regards.