N writing a chemical equation that produces hydrogen gas, the correct representation of hydrogen gas is

Minchanka [31]

You multiply the number of atoms by 12 to get how many electrons (since each atom has 12 electrons in it)
you multiply the number of atoms by 13 to get how many neutrons
(since each atom of this isotope has 13 neutrons in it)

5 0

3 years ago

Which of the following has the largest radius? Answer:K

mixas84 [53]

Answer:

the answer is k? lol thanks

4 0

3 years ago

The reactants of two chemical equations are listed.

hjlf

The correct answer is b

8 0

3 years ago

Determine the volume of a 0.800 M K2Cr2O7 solution required to completely react with 4.24 g of Cu.

Pachacha [2.7K]

Answer: The volume of solution required is 0.0275 L.

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass of copper = 4.24 g

Molar mass of copper = 63.55 g/mol

Putting values in above equation, we get:

$\text{Moles of copper}=\frac{4.24g}{63.55g/mol}=0.067mol$

The chemical equation for the reaction of potassium dichromate and copper follows:

$K_2Cr_2O_7+3Cu+7H_2SO_4\rightarrow 3CuSO_4+Cr_2(SO_4)_3+K_2SO_4+7H_2O$

By Stoichiometry of the reaction:

3 moles of copper reacts with 1 mole of potassium dichromate.

So, 0.067 moles of copper will react with = $\frac{1}{3}\times 0.067=0.022mol$ of potassium dichromate

To calculate the volume of potassium dichromate, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}$

We are given:

Moles of potassium dichromate = 0.022 mol

Molarity of solution = 0.800 M

Putting values in above equation, we get:

$0.08mol/L=\frac{0.022mol}{\text{Volume of solution}}\\\\\text{Volume of solution}=0.0275L$

Hence, the volume of solution required is 0.0275 L.

6 0

3 years ago

You are asked to prepare 500. mL 0.150 M acetate buffer at pH 5.10 using only pure acetic acid ( MW = 60.05 g/mol, p K a = 4.76

Amanda [17]

Answer:

4.504g of acetic acid

Explanation:

The acetic acid in reaction with NaOH produce acetate ion, thus:

CH₃COOH + NaOH → CH₃COO⁻ + H₂O + Na⁺

That means the moles of acetate buffer comes, in the first, from the acetic acid

As you need 500mL (0,500L) of a 0.150M acetate buffer, moles are:

0.500L × (0.150mol / 1L) = 0.075 moles of acetate. That is:

0.075mol = [CH₃COO⁻] + [CH₃COOH]

Thus, grams of acetic acid you need to prepare the buffer are:

0.075 moles acetic acid × (60.05g / 1mol) = 4.504g of acetic acid

6 0

3 years ago