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klasskru [66]
3 years ago
15

Correct answer. 9. The mass number of an element is the number of? ​

Chemistry
1 answer:
Elis [28]3 years ago
4 0

Answer:

The mass number is defined as the total number of protons and neutrons in an atom. The number of neutrons = mass number − atomic number.

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Grey Goose ® vodka has an alcohol content of 40.0 % (v/v). Assuming that vodka is composed of only ethanol and water answer the
Vitek1552 [10]

Explanation:

Grey Goose vodka has an alcohol content of 40.0 % (v/v).

Volume of vodka = V = 100 mL

This means that 40.0 mL of alcohol is present 100 mL of vodka.

Volume of ethanol=V' = 40.0 mL

Mass of ethanol = m

Density of the ethanol = d = 0.789 g/mL

m=d\times V' = 0.789 g/ml\times 40.0 mL=31.56 g

Volume of water = V''= 100 ml - 40.0 mL = 60.0 mL

Mass of water = m'

Density of the water = d' = 1.00 g/mL

m'=d'\times V'' = 1.00 g/ml\times 60.0 mL=60.0 g

a.)

Moles of ethanol = n= \frac{31.56 g}{46g/mol}=0.6861 mol

Volume of vodka = V = 100 mL = 0.100 L ( 1mL=0.001 L)

Molarity of the ethanol:

=\frac{0.6861 mol}{0.100 L}=6.861 M

6.861 M the molarity of ethanol in this vodka.

b) Mass of ethanol = 31.56 g

Moles of ethanol = n= \frac{31.56 g}{46g/mol}=0.6861 mol

Volume of vodka = V = 100 mL

Mass of vodka = m

Density of the water = D = 0.935 g/mL

M=D\times V=0.935 g/ml\times 100 ml=93.5 g

The percent by mass of ethanol % (m/m):

\frac{31.56 g}{93.5 g}\times 100=33.75\%

33.75% is the percent by mass of ethanol % (m/m) in this vodka.

c)

Moles of ethanol = n= \frac{31.56 g}{46g/mol}=0.6861 mol

Mass of solvent that is water = 60.0 g = 0.060 kg ( 1g = 0.001 kg)

Molality of ethanol in vodka :

m=\frac{0.6861 mol}{0.060 kg}=11.435 m

11.435 m is the molality of ethanol in this vodka.

d)

Moles of ethanol = n_1=\frac{31.56 g}{46g/mol}=0.6861 mol

Moles of water = n_2=\frac{60.0 g}{18 g/mol}=3.333 mol

Mole fraction of ethanol = \chi_1

\chi_1=\frac{n_1}{n_1+n_2}=\frac{0.6861 mol}{0.6861 mol+3.333 mol}

= 0.1707

Mole fraction of water = \chi_2

\chi_2=\frac{n_2}{n_1+n_2}=\frac{3.3333 mol}{0.6861 mol+3.333 mol}

= 0.8290

e)

The vapor pressure of vodka = P

Mole fraction of ethanol = \chi_1=0.1707

Mole fraction of water = \chi_2=0.8290

The vapor pressures of ethanol  = p_1=45.0 Torr

The vapor pressures of pure water = p_2=23.8Torr

P=\chi_1\times p_1+\chi_2\times p_2

P=0.1707\times 45.0torr+0.8290\times 23.8 Torr=27.41 torr

The vapor pressure of vodka is 27.41 Torr.

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3 years ago
Using the periodic table, complete the following.
vladimir1956 [14]
Molecular weight= 1.00784 u
mass of one mole = 1.008 grams

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3 years ago
Significant digits of 1.0 x 10^-2
son4ous [18]

There's two sig figs: the 1 and the zero. The 10^-2 contributes no sig figs.

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Which of the following are strong electrolytes in water?
m_a_m_a [10]

Answer:

Ionic compounds that ionize completely in water

8 0
3 years ago
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How many total moles of gas are there in the reactants and how many total moles of gas are there in the products?
anygoal [31]

Total moles of gas in the reactants: 4

Total moles of gas in the products: 2

7 0
2 years ago
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