Is Matter Around Us Pure? — Science STD 9 — Question

How can you obtain pure water from a salt-water mixture (or salt-solution)? Draw a meat and labelled diagram of the apparatus you would use to obtain pure water from a salt-water mixture (or salt-solution).

What would happen to the life of a cell if there was no Golgi apparatus?

A, B and C are all liquids. Liquid A has a comparatively low boiling point. On heating, liquid a vaporizes completely without leaving behind any residue. Liquid A is being used increasingly as a fuel in motor vehicles either alone or by mixing with petrol. Liquid B has a very high boiling point. It also vaporizes completely on heating, without leaving any residue. Liquid B is a conductor of electricity and used in making thermometers. Liquid c has a moderate boiling point. On heating, liquid C vaporises leaving behind a white solid D which is used in cooking vegetables. The condensation of vapours from C give a liquid E which turns anhydrous CuSO₄ to blue.

1. Which liquid could be an element? Name this element.
2. Which liquid could be a mixture? Name this mixture.
3. Which liquid could be a compound? Name this compound.
4. What could the solid D be?
5. What do you think is liquid E?

Write the differences between mass and weight of an object.

How do you differentiate between capture fisheries, inland fisheries and aquaculture?

Define connective tissue. Write down functions of connective tissue.

There are four substances W, X, Y and Z. The substance W is a dark violet solid having diatomic molecules. A solution of W in alcohol is used as a common antiseptic C. The substance X is a white solid which is usually recovered from sea water on a large scale. The substance Y is a white solid which is insoluble in water and used in the form of small balls for the safe storage of woollen clothes. The substance Z is a yet another white solid which is used in making commonly used dry cells.

1. Name (i) W (ii) X (iii) Y and (iv) Z.
2. Out of W, X, Y and Z, which substance/ substances can undergo sublimation?
3. Which substances organic in nature?
4. What is the name of substance C?
5. Which substance belongs to the halogen family?

In a reaction, 5.3g of sodium carbonate reacted with 6g of acetic acid. The products were 2.2g of carbon dioxide, 0.9g water and 8.2g of sodium Q acetate. Show that these observations are in agreement with the law of conservation of mass. sodium carbonate + acetic acid → sodium acetate + carbon dioxide + water.