A mixture of 5 gases exerts a pressure of 101.8 kPa. The pressure exerted by hydrogen gas is 40.8 kPa, by bromine gas is 26.7 kPa, by Fluorine gas is 3.5 kPa, and by helium gas is 12.7 kPa. What is the pressure exerted by the final gas?

The pressure exerted by the final gas is 18.1 kPa

Explanation:

We note that according to Dalton's law of partial pressure, the pressure a=exerted by a mixture of gases is equal to the sum of the partial pressures of the individual gases in the mixture

The gases and their partial pressures are;

Hydrogen = 40.8 kPa

Bromine = 26.7 kPa

Fluorine = 3.5 kPa

Helium = 12.7 kPa

Final gas pressure = required

Therefore,

40.8 + 26.7 + 3.5 + 12.7 + Final gas pressure = 101.8 kPa

83.7 kPa + Final gas pressure = 101.8 kPa

Final gas pressure = 101.8 kPa - 83.7 kPa = 18.1 kPa

The pressure exerted by the final gas = 18.1 kPa.

assuming that your periodic table has eighteen columns, you should highlight   the four elements in the third column from the left of the table.

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potassium has electron configuration and calcium . the s orbital of a main shell holds a maximum of two electrons. the next element would thus have the electron configuration and satisfy the requirements.

a neutral atom of the element contains three electrons on top of the most recent noble gas element. it should thus be placed in the third column of the periodic table. both scandium and yttrium would satisfy the conditions. an aufbau diagram indicates that the 4f orbital is filled before the 5d. however, it appears that exceptions exists for both lanthanum and actinium. neutral atoms of the two d-block elements also demonstrate the and should be highlighted as well.