Matter in Our Surroundings — Science STD 9 — Question

The common characteristics of solid and liquid states are:

Which of the following obeys the law of constant proportions in their formation:

Two chemical substances X and Y combine together to form a product P which contains both X and Y
X + Y → P
X and Y cannot be broken down into simpler substances by simple chemical reactions. Which of the following statements concerning X, Y and P are correct?

1. P is a compound.
2. X and Y are compound.
3. X and Y are elements.
4. P has a fixed composition.

1. (i), (ii) and (iii)
2. (i), (ii) and (iv)
3. (ii), (iii) and (iv)
4. (i), (iii) and (iv)

Four students A, B, C and D verified the law of conservation of mass by performing chemical reaction between barium chloride and sodium sulphate. All of them took 107.2g barium chloride solution and 116.1g of sodium sulphate solution and mixed them in the beaker of mass 150g. They reported their results as follows:

Students	Colour of reaction mixture after mixing	Mass of reation mixture in the beaker including mass of beaker
A	White Precipitate	383.3g
B	BrownPrecipitate	393.3g
C	WhitePrecipitate	373.3g
D	Brown Precipitate	363.3g

The correct observation is that of student.

Barium chloride reacts with sodium sulphate to form Barium sulphate and sodium chloride. Then, according to the law of conservation of mass:

Which of the following statements are true for pure substances?

1. Pure substances contain only one kind of particles.
2. Pure substances may be compounds or mixtures.
3. Pure substances have the same composition throughout.
4. Pure substances can be exemplified by all elements other than nickel.

1. (i) and (ii)
2. (i) and (iii)
3. (iii) and (iv)
4. (ii) and (iii)

Filtration as a method of separation can be used for:

On converting 308K, 329K and 391K to Celsius scale, the correct sequence of temperatures will be:

The formula unit mass of a substance is the:

The cation of an element has: