Carbon dioxide is usually prepared in laboratory by the action of dilute hydrochloric acid on
Marble chips
Caustic soda
Slaked lime
Table salt
Which is the smallest identifiable unit of a compound?
Atom
Molecule
Mole
Ion
Iron sulphate + aluminium -----> aluminium sulphate + ironThe above reaction is an example of a:
Combination reaction
Decomposition reaction
Dissolution reaction
Displacement reaction
The purest solid form of a substance having a definite geometrical shape is called
Crystal
Precipitate
Precipitates formed in a chemical reaction
Escapes as bubbles
Settles down at the bottom
Forms a solution
All of the above
Impure substances are commonly called:
Mixtures
Compounds
Solutions
We can separate soil and water from mud by the process of:
Crystallization
Decomposition
Filtration
Burning of magnesium ribbons in presence of oxygen(air) is an example of reaction like
Combination
Dissolution
Which of the following combine to form water molecules?
Hydrogen, carbon
Hydrogen, oxygen
Carbon, oxygen
Nitrogen, oxygen
A precipitate in a reaction is usually represented by an arrow
Downward
Upward
Horizontal
Diagonal