Answer:
Explanation:
mass of 1mole of brick = mass of 1 brick x avagadro number
= 4 kg x 6.022 x 10^23 bricks = 2.4 x 10^24 kg
No. of moles of bricks have a mass equal to the mass of the earth
= mass of earth / mass of 1 mole of brick
= [ 6 x 10^27 ] / [ 2.4 x 10^24 ]
= 2.5 x 10^3
= 2500 moles
Answer:
The correct answer is option 2.
Explanation:
Colligative property is defined as property which depends upon only on the numbers of particles of solute dissolved in definite amount of solvent, It do not depend on the nature of the solute.
For example : NaCl solution with 0.4 molal will show same colligative properties as a that of the glucose solution with 0.04 molal concentration.
The following are the examples of colligative property:
1. Relative lowering of vapor pressure.
2. Osmotic pressure
3. Elevation in boiling points
4. Depression in freezing point
Answer:
Ionic bonds are formed through the exchange of valence electrons between atoms, typically a metal and a nonmetal. The loss or gain of valence electrons allows ions to obey the octet rule and become more stable. Therefore, ions combine in ways that neutralize their charges.
Explanation:
Answer:
The specific heat capacity of glass is 0.70J/g°C
Explanation:
Heat lost by glass = heat gained by water
Heat lost by glass = mass × specific heat capacity (c) × (final temperature - initial temperature) = 58.5×c×(91.2 - 21.7) = 4065.75c
Heat gained by water = mass × specific heat capacity × (final temperature - initial temperature) = 250×4.2×(21.7 - 19) = 2835
4065.75c = 2835
c = 2835/4065.75 = 0.70J/g°C