Science : Ch 03 – Metals and Non-metals

The solution of one of the following compounds will not conduct electricity. This compounds is:

Which of the subsequent oxide(s) of iron would be obtained on prolonged reaction of iron with steam?

Which among the following Declaration is incorrect for magnesium metal?

An element A is mushy and can be cut with a knife. This is very reactive to air and cannot be kept in open air. It reacts vigorously with water. Identify the element from the following:

Although metals form basic oxides, which of the subsequent metals form an amphoteric oxide?

In the given reaction, Al₂O₃ + NaOH → …X… + H₂O. What is element X?

Which of the consecutive are not ionic compounds?

• KCl
• HCl
• CCl₄
• NaCl

2 ml each of conc. HCl, HNO₃, and a mixture of conc. HCl and conc. HNO3 in the ratio of 3:1 were taken in test tubes labelled as : A, B and C. A small piece of metal was put in each test tube. No change occurred in test tubes A and B but the metal got dissolved in test tube C. The metal could be:

1. AI
2. Au
3. Cu
4. Pt

Hydrogen gas is not evolved when a metal reacts with nitric acid because

Name a metal that have very low melting points.

Why do ionic compounds conduct electricity in molten state? Because

The Lustrous non-metal

Metal that is best conductor of electricity

Give the formula of the stable binary compounds that would be formed by the combination of following pair of elements: Li and O₂

When a metal X is treated with cold water, it gives a basic salt Y with molecular formula XOH (molecular mass = 40) and liberates a gas Z which easily catches fre. Identify X, Y and Z.