2 . a) b) (1) List three oxides of nitrogen ( 3ks) State Charles law (2mks) (111) A given mass of gas occupies 300cm at 900mmHg if temperature remains constant (5mks) State one industrial application in each of the following Crystallization (2mks) (11) Filtration (2mks) (111) Fractional distillation (2mks) (1) State the property of hydrogen which makes it suitable for filling meteorological balloons (2mks) Why is helium preferred to hydrogen in filling balloons? (2mks) (1) с) 3. a) b) (1) List the steps involved in the purification of water for town supply State two differences between rusting and burning (1) Copy and complete the following table Element No of neutron Electron Group configuration 1 1522522p5 ZOR (ii) State the family to which the elements belong State the two differences between fine chemical and heavy chemicals 32P 130 19 c) 1. a ( List the three types of particles present in an atom Name the element that does not contain all the three particles What is the particle that is not present What is isomerism? b)​

1.) which of the following is a molecule but not a compound? a.he b.f2 c.h2o d.ch4 2.) what is a physical combination of substances? a.a compound b.a molecule c.a mixture d.an element 3.) what is a chemical combination of substances? a.a compound b.an atom c.a mixture d.an element 4.) what is the relationship between the solute and solvent in a solution? a.they form a compound b.they form a mixture c.they form molecules d.they form chemical bonds 5.) the gases in air dissolve in water. what would be one way to reduce the amount of a gas dissolved in water? a.add more water b.reduce the air pressure c.increase the air pressure d.stir the water 6.) how would you determine the solubility of a substance? a.find how well it dissolved various substances. b.find the mass and the volume of the substance. c.find the temperature at which the substance evaporated. d.find how much i was able to dissolve in a solute. 7.) the periodic table organizes all of the kinds of a.molecules. b.compounds. c.atoms. d.ions. 8.)what distinguishes two substances combined to become a compound vs. two substances combined to become a mixture? a.whether they can be easily separated b.whether they chemically bond together c.whether they both are visible d.whether they are heterogeneous 9.) the principle components of air are: n2 78% o2 21% ar 0.95% co2 0.038% this is a solution of a.molecules and atoms. b.molecules. c.compounds and molecules. d.atoms.