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3 years ago

What is the number of electrons in the highest principle energy level of an

Chemistry

1 answer:

Margarita [4]3 years ago

3 0

Answer:

8 electrons

Explanation:

as the the 1st period (H and He), it can hold up to 2 electrons. in the 2nd period (Li, Be, B, C, N, O, F and Ne), it can hold up to 8 electrons. Itstops at 6 when it reached O. add the lelectrons that you have

2+6=8

8 electrons

You might be interested in

Write the empirical formula for at least four ionic compounds that could be formed from the following ions

andreyandreev [35.5K]

Answer:

NH₄CN, NH₄IO₃, Fe(CN)₃, Fe(IO₃)₃

Explanation:

Cations (positively charged ions) can only form ionic bonds with anions (negatively charged ions). However, you can't just simply put one cation and one anion together to form a compound. Each compound needs to been neutral, or have an overall charge of 0. When cations and anions do not have charges that perfectly cancel, you need to modify the amount of each ion in the compound.

1.) NH₄CN

-----> NH₄⁺ and CN⁻

-----> +1 + (-1) = 0

2.) NH₄IO₃

-----> NH₄⁺ and IO₃⁻

-----> +1 + (-1) = 0

3.) Fe(CN)₃

-----> Fe³⁺ and CN⁻

-----> +3 + (-1) + (-1) + (-1) = 0

4.) Fe(IO₃)₃

-----> Fe³⁺ and IO₃⁻

-----> +3 + (-1) + (-1) + (-1) = 0

3 0

2 years ago

WHAT MASS OF 1,1 DICHLOROEHTANE MUST BE MIXED WITH 100G OF 1,1 DICHLOROTETRAFLUOROEHTANE TO GIVE A SOLUTION WITH VAPOR PRESSURE

vaieri [72.5K]

This is an incomplete question.

The complete question is:

1,1-dichlorotetrafluoroethane, CF3CCL2F, has a vapor pressure of 228 torr. What mass of 1,1-dichloroethane must be mixed with 100.0 g of 1,1-dichlorotetrafluoroethane to give a solution with vapor pressure 157 torr at 25 degrees celsius?

Answer: 46.9 g of 1,1 dichloroethane must be fixed with 100 g of 1,1 dichlorotetrafluoroethane to give a solution with vapor pressure of 157 torr at $25^0C$

Explanation:

As the relative lowering of vapor pressure is directly proportional to the amount of dissolved solute.

The formula for relative lowering of vapor pressure will be,

$\frac{p^o-p_s}{p^o}=i\times x_2$

where,

$\frac{p^o-p_s}{p^o}$ = relative lowering in vapor pressure

i = Van'T Hoff factor = 1 (for non electrolytes)

$x_2$ = mole fraction of solute

= $\frac{\text {moles of solute}}{\text {total moles}}$

Given : x g of solute is present in 100 g of solvent

moles of solute (1,1 DICHLOROEHTANE) = $\frac{\text{Given mass}}{\text {Molar mass}}=\frac{xg}{98.96g/mol}moles$

moles of solvent (1,1 DICHLOROTETRAFLUOROEHTANE ) = $\frac{\text{Given mass}}{\text {Molar mass}}=\frac{100g}{170.92g/mol}=0.58moles$

Total moles = moles of solute + moles of solvent = $\frac{xg}{98.96g/mol}+0.58$

$x_2$ = mole fraction of solute = $\frac{\frac{xg}{98.96g/mol}}{\frac{xg}{98.96g/mol}+0.58}$

$\frac{228-157}{157}=1\times \frac{\frac{xg}{98.96g/mol}}{\frac{xg}{98.96g/mol}+0.58}$

$0.45=1\times \frac{\frac{xg}{98.96g/mol}}{\frac{xg}{98.96g/mol}+0.58}$

$x=46.9g$

Thus 46.9 g of 1,1 dichloroethane must be fixed with 100 g of 1,1 dichlorotetrafluoroethane to give a solution with vapor pressure of 157 torr at $25^0C$

5 0

4 years ago

When 70.4 g of benzamide (C7H7NO) are dissolved in 850. g of a certain mystery liquid X , the freezing point of the solution is

lora16 [44]

Answer:

i=1.62 .

Explanation:

Let, i be the Van't Hoff Factor.

Moles of benzamide,= $\dfrac{Mass}{molar\ mass}=\dfrac{70.4}{121.14}=0.58\ mol.$