Carbon and its Compounds — Science STD 10 — Question

Complete the reaction: 2FeSO₄ →  Fe₂O₃  + ____ + ____.

Which of the following reactions is an example of endothermic reaction?

Which component is getting reduced in the following reaction: MnO₂ + 4HCl → MnCl₂ + 2H₂O + Cl₂

A student took four test tubes P, Q, R and S and filled about 8 mL of distilled water in each. After that he dissolved an equal amount of Na₂SO₄ in P, K₂SO₄ in Q, CaSO₄ in R and MgSO₄ in S. On adding an equal amount of soap solution and shaking each test tube well, a good amount of lather will be obtained in the test tubes:

Which of the following can damage optic nerve leading to blindness, if taken internally?

An element E reacts with water to form a solution which turns phenolphthalein solution pink. The element E is most likely to be:

1. S
2. Ca
3. C
4. Ag

The salt whose aqueous solution will turn blue litmus to red is:

Which among the following alloys contain mercury as one of its constituents?

1. Stainless steel.
2. Alnico.
3. Solder.
4. Zinc amalgam.

The atomic number of an element is 20. In modern periodic table, this element is placed:

1. 2^nd period.
2. 4^th period.
3. 3^rd period.
4. 1^st period.

Which of the following is not a mineral acid?