JAVAHAR NAVODAY
I.I.T. FOUNDATION
Class : VII Marks: 25
Sub : Chemistry Time: 45 Mts -----------------------------
I. Carbon burns with Oxygen. 3 x 1 = 3
1) How much amount of Oxygen is required ?
2) How many atoms of Carbon is required to libereate 6.023 x 1023 molecules of Carbondioxide ?
3) How much volume of Carbondioxide is liberated when 6 gm of Carbon reacts with Oxygen ?
II. Calcium Carbonate reacts with dilute Hydrochloric acid. 3 x 1 = 3
4) How many moles of Carbondoxide is liberated when 100gm of Calcium Carbonate is treated with dilute Hydrochloric acid ?
5) How many molecules of Calcium carbonate reacts with 2 moles of Hydrochloric acid ?
6) How much volume of Carbondoxide liberate when 10 gm of Calcium Carbonate reacts with Hydrochloric acid ?
III. Hydrogen burns with Oxygen. 4 x 1 = 4
7) How many grams of Hydrogen is required ?
8) How many volumes of Hydrogen is required ?
9) How many moles of Oxygen is required ?
10) How much volume of Oxygen is required to react with 1.2 gms of Hydrogen ?
IV. Write P for the physical change and C for the chemical change in the blank space on the right for the following changes. 11 x 1 = 11
11) Formation of dew.
12) Evaporation of water.
13) Rusting of iron.
14) Sublimation of camphor.
15) Digestion of food
16) Making of ice cream.
17) Breaking of glass pane.
18) Smoking of cigarette
19) Decomposition of water into hydrogen and oxygen.
20) Melting of wax.
21) Burning of magnesium in air.

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