or
  1. Atomic no. (Z) = 13 and atomic mass (A) = 27
    No. of neutrons = A-Z = 27 - 13 = 14
    No. of electrons = 13 - 3 = 10

    Al atom loses 3e- to form Al+3.

  2. The permanent change in which one compound is transformed into other compound have different properties is known as chemical change.

    Two important characters are:

    a. It is irreversible change.
    b. New compound having different properties are formed.


  3. Atomic no. (Z) = 19 and Atomic mass (A) = 39
    No. of neutrons = (A - Z) = (39 - 19) = 20
    No. of electrons = Number of protons = Atomic number

Which of the elements listed below was called in honor of a country?

Which is the example of hydrolysis reaction?

What is the symbol for tungsten?

The name of the chemical compound N2O is

Potassium manganate has the formula

Which statement is erroneous?

Which of the elements given below was called in honor of a continent?

According to the current definition, 1amu corresponds to

Approximate atomic weight of an element is 26.89. If its equivalent weight is 8.9, the exact atomic weight of element would be

The number of moles present in 6 gm of carbon is:

What is the concentration of nitrate ions if equal volumes of 0.1 M AgNO3 and 0.1 M NaCl are mixed together

The -ve charged particles is called:

What is the normality of a 1 M solution of H3PO4

The total number of ions present in 111 g of CaCl2 is

Which of the following weighs the most?

Under similar conditions of pressure and temperature, 40 ml of slightly moist hydrogen chloride gas is mixed with 20 ml of ammonia gas, the final volume of gas at the same temperature and pressure will be

An organic compound contains carbon , hydrogen and oxygen. Its elemental analysis gave C, 38.71% and H, 9.67%. The empirical formula of the compound would be

Which of the following cannot give iodometric titrations

What is the concentration of nitrate ions if equal volumes of 0.1 MAgNO3 and 0.1 M NaCl are mixed together

The number of moles present in 6 gms of carbon is:

Which of the following contains same number of carbon atoms as are in 6.0 g of carbon (C – 12)?

A symbol not only represents the name of the element but also represents

Atomic weight of an element is not necessarily whole number because