Heredity and Evolution — Science STD 10 — Question

How would the tendency to gain electrons change on moving from left to right in a period of the periodic table?

Name the phenomenon responsible for the following effect:
When we sit in front of a plane mirror and write with our right hand, it appears in the mirror that we are writing with the left hand.

Write the chemical formula of:

1. Soda ash, and
2. Sodium carbonate decahydrate.

Name two elements whose properties were predicted on the basis of their positions in Mendeleev’s periodic table.

What is the difference between two consecutive homologues:

1. In terms of molecular mass?
2. In terms of number and kind of atoms per molecule?

Give the composition of an alloy called solder. State its one property and one use.

What special name is given to the corrosion of iron?

Which one of these circumstances enables a concave mirror to be used as a shaving mirror?

Which non-metal has been placed in the reactivity series of metals?