Chemical Reactions and Equations — Science STD 10 — Question

An element is soft and can be cut with a knife. It is very reactive and cannot be kept open in the air. It reacts vigorously with water. The element is most likely to be:

NaHCO, formed by reaction of:

Which of the following statements are correct regarding isomers?
I. Isomers have same structural formula.
II. Isomers have same molecular formula.
III. Isomers have same chemical properties.
IV. The compound C₃⁢H₈ has no isomers.

Generally, non-metals are not conductors of electricity. Which of the following is a good conductor of electricity?

1. Diamond.
2. Graphite.
3. Sulphur.
4. Fullerene.

Carbon's electronic configuration is:

The colour of methyl orange indicator in a solution is yellow. The pH of this solution is likely to be:

1. 7
2. Less than 7
3. 0
4. More than 7

Out of KCl, HCl, CCl₄ and NaCl, the compounds which are not ionic are:

1. KCl and HCl.
2. HCl and CCl₄.
3. CCl₄ and NaCl.
4. KCl and CCl₄.

Which of the following statements about the Modern Periodic Table is correct:

1. It has 18 horizontal rows known as Periods.
2. It has 7 vertical columns known as Periods.
3. It has 18 vertical columns known as Groups.
4. It has 7 horizontal rows known as Groups.

Which of the following statements about graphite and diamond is true?

The formula of baking soda is: