Explain why the size of an atom tends to increase from top to bottom<br> within a group?

18 An important environmental consideration is the appropriate disposal of cleaning solvents. An environmental waste treatment c

Katyanochek1 [597]

Answer:

a) Percentage by mass of carbon: 18.3%

Percentage by mass of hydrogen: 0.77%

b) Percentage by mass of chlorine: 80.37%

c) Molecular formula: $C_{2} H Cl_{3}$

Explanation:

Firstly, the mass of carbon must be determined by using a conversion factor:

$0.872g CO _{2} *\frac{12g C}{44g CO_{2} } = 0.238g CO_{2}$

The same process is used to calculate the amount of hydrogen:

$0.089g H_{2}O*\frac{2g H}{18g H_{2}O } = 0.010g H$

The percentage by mass of carbon and hydrogen are calculated as follows:

%C $\frac{0.238g}{1.3g} *100%$ = 18.3%

%H $\frac{0.010g}{1.3g} *100%$ =0.77%

From the precipation data it is possible obtain the amount of chlorine present in the compound:

$1.75 AgCl*\frac{35.45g Cl}{143.45g AgCl}$ = 0.43g AgCl

Let's calculate the percentage by mass of chlorine:

%Cl= $\frac{0.43g}{0.535g} * 100%$ = 80.37%

Assuming that we have 100g of the compound, it is possible to determine the number of moles of each element in the compound:

$18.3g C*\frac{1mol C}{12g C} = 1.52mol C$

$0.77g H*\frac{1mol H}{1g H} = 0.77mol H$

$80.37gCl*\frac{1molCl}{35.45g Cl} = 2.27mol Cl$

Dividing each of the quantities above by the smallest (0.77mol), the subscripts in a tentative formula would be

$C=\frac{1.52}{0.77} = 1.97$ ≈ 2

$H = \frac{0.77}{0.77} = 1$

$Cl =\frac{2.27}{0.77}=2.94$ ≈3

The empirical formula for the compound is:

$C_{2} H Cl_{3}$

The mass of this empirical formula is:

mass of C + mass of H + mass of Cl= 24g +1+ 106.35 =131.35g

This mass matches with the molar mass, which means that the supscript in the molecular formula are the same of the empirical one.

5 0

3 years ago

What happens when the vapor pressure of a liquid is equal to the external pressure? The liquid freezes The intermolecular forces

Makovka662 [10]

Answer:

The liquid boils.

Explanation:

Vapor pressure is simply defined as the pressure exerted on a substance (solid/liquid) by the vapor of the substance collected just at the top of the surface of the substance. In concise words, it is the pressure of Vapor that is in contact with its solid or liquid state.

For a liquid, it is the pressure of the Vapor gathering at the top of the surface of the liquid.

When this Vapor pressure matches the external pressure, the temperature stays constant and the molecules of the liquid all through the liquid can gain enough energy, rise to the surface of the liquid and break free in gaseous form; thereby, boiling.

The definition of boiling point basically explains that it is the point at which temperature stays constant, and the vapour pressure of the liquid matches the atmospheric/external pressure around the liquid and its liquid molecules change into vapor.

This is why liquids boil faster at higher altitudes; the atmospheric pressure at higher altitudes is reduced, hence, the temperature at which liquid boils at this high altitude is normally lower than its known boiling point temperature.

It is also why food cooks to a temperature higher than the boiling point of water in a pressure cooker/pot. The added pressure ensures that the cooking water boils at temperatures higher than its boiling point; thereby exposing the cooking ingredients to a higher temperature, leading to faster cooking.

Hence, it is obvious why boiling is the answer to this question.

6 0

3 years ago

What is the total number of valence electrons in the dot structure of CBr4? Explain how you determined this answer. What is the

Mnenie [13.5K]

Answer:- There are 32 valence electrons and it's tetrahedral in shape.

Explanations:- Atomic number of carbon is 6 and it's electron configuration is $1s^22s^22p^2$ . It has 4 electrons in the outer most shell means it has 4 valence electrons.

Atomic number of Br is 35 and it's electron configuration is $1s^22s^22p^63s^23p^64s^23d^1^04p^5$ . It has 7 electrons in the outer most shell(2 in 4s and 5 in 4p) .

There is one C and four Br in the given compound. So, total number of valence electrons = 4+4(7) = 4+28 = 32

Four Br atoms are bonded to the central carbon atom and also there isn't any lone pair present on carbon. It makes it tetrahedral.

5 0

3 years ago

How do oil spills affect marine ecosystems?

charle [14.2K]

Oil makes it impossible for fur-bearing mammals to insulate<span>, this leaves them unprotected from the harsh elements out in the water. Birds and mammals will die from hypothermia without the ability to insulate from the freezing water.

I hope this helps you! :-)</span>

3 0

3 years ago

A student must make a 3 m acid solution using a 5 m acid solution. which of these is the safest way to make the solution?

weqwewe [10]

The motivation to abstain from adding water to concentrated acids is that, with a few acids, amid weakening, a considerable measure of warmth is discharged, by adding the corrosive to the water, the generally extensive measure of water will retain the warmth. On the off chance that you added water to concentrated corrosive when you initially beginning pouring the water, it could get sufficiently hot for the little measure of water that was filled all of a sudden bubble and splatter corrosive on you. Concentrated sulfuric corrosive is most famous for doing this, not all acids get that hot on weakening, but rather in the event that you make a propensity for continually adding the corrosive to water for every one of them, you can't turn out badly.

8 0

4 years ago

Explain why the size of an atom tends to increase from top to bottom within a group?