All Questions

A given mass of gas T diffuses through a porous plug in 48 seconds while a similar mass of gas R diffuse in 70 seconds. Given that the density of gas T is 0.6g/cm3, find the density of gas R (2mks)

Describe an experiment that can be used to determine whether a given sample of a liquid is pure (2mks)

Element W has two isotopes W - 36 and W - 40 which occur in the ratio X:4. Given that R.A.M of W is 37.25, find the value of X                          (2mks)

Gas X and Y can be collected as shown below

(a) Name the method used to collect gas Y                     (1mk)

 

 

(b) How do densities of gas X and gas Y compare?                (1mk)

 

 

(c) Give an example of a gas that can be collected using the same method as gas Y     (1mk)

In the industrial manufacture of Ammonia one of the raw materials is nitrogen gas

(a) Name one other raw material                              (1mk)

 

 

(b) Name two possible sources of the raw material you have named in (a) above  (2mks)

 

 

 

(c) Name two substances that can be used as catalyst in this process             (2mks)

 

 

(d) State one use of ammonia                            (1mk)

Few drops of hydrochloric acid were added into a test tube containing lead (II) Nitrate solution

(a) State one observation made               (1mk)

 

 

(b) Write an ionic equation of the reaction that occurred in the test tube                   (1mk)

When 20g of a compound containing carbon, hydrogen and oxygen was burnt in the air, 29.3g of carbon (IV) oxide and 11.7g of water were produced. Determine its empirical formulae. (C=12, H=1 , O=16)        (3mks)

Using dots (.) and crosses (x) , show bonding in carbon(II) oxide                     (2mks)

A compound can be represented as

(a) What name is given to the above class of compounds                   (1mk)

 

 

(b) Name two reagents that can be reacted together to generate the above compound      (2mks)

 

 

(c) State two conditions necessary for the reaction leading to formation of the above compound to occur (2mks)

Chlorine is commonly used in the manufacture of Ca (OCl)2

(i) State one use of the above compound of chlorine                     (1mk)

 

 

(ii) Write a chemical equation leading to the production of Ca (OCl)2 (1mk)