Answer:
All matter is made up of tiny particles called <em><u>a</u></em><em><u>t</u></em><em><u>o</u></em><em><u>m</u></em><em><u>s</u></em><em><u>.</u></em> Atoms are made up of three subatomic particles known as <em><u>proton</u></em><em><u>,</u></em><em><u> </u></em><em><u>neutron</u></em><u> </u>and<em><u> </u></em><em><u>electron</u></em><em><u>.</u></em> Protons and neutrons are located in the <em><u>nucleus</u></em><em><u>.</u></em>
The nucleus is dense and takes up very little space within the atom. All protons have a <em><u>positive</u></em><em><u> </u></em>charge and have a mass of about 1 amu. All neutrons have no charge or are <em><u>neutral</u></em> and have a mass of about 1 amu.
Electrons are located in the area known as electron cloud. Electrons orbit around the nucleus and have a <em><u>negative</u></em> charge
Explanation:
The pressure exerted by vapors or gas on the surface of a liquid is known as vapor pressure.
This means that weaker is the intermolecular forces present in a substance more easily it can form vapors. As a result, it will have high vapor pressure.
As substance B has high vapor pressure which means that it has weak intermolecular forces.
Also, stronger is the intermolecular forces present in a substance more will be its boiling point. Hence, more energy or temperature is required to break the bonds. Hence, substance A has higher boiling point and high heat of vaporization.
When surrounding pressure is less than or equal to its vapor pressure then substance B boils into the gas phase. Hence, substance B will be a gas at 300 mm Hg.
Therefore, we can conclude that characteristics of the two substances will be as follows.
(a) Substance B - has weaker intermoclcular
(b) Substance A - has a higher boiling point
(c) Substance B - is a gas at 300 mm Hg
(d) Substance A - has a higher heat of vaporization
Answer: The empirical formula for the given compound is 
Explanation : Given,
Percentage of H = 18 %
Percentage of N = 82 %
Let the mass of compound be 100 g. So, percentages given are taken as mass.
Mass of H = 18 g
Mass of N = 82 g
To formulate the empirical formula, we need to follow some steps:
Step 1: Converting the given masses into moles.
Moles of Hydrogen = 
Moles of Nitrogen = 
Step 2: Calculating the mole ratio of the given elements.
For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 5.8 moles.
For Hydrogen = 
For Nitrogen = 
Step 3: Taking the mole ratio as their subscripts.
The ratio of H : N = 3 : 1
Hence, the empirical formula for the given compound is
Number of mole : mass/ molar mass
87g/ (2 x 16) = 2.719 mol
volume = number of mole x molar volume
volume = 2.719 x 22.4
volume = 60.906 L
