Advertisements
Advertisements
Question
Calculate the mass of 3.011 × 1024 atoms of carbon.
Solution
Number of carbon atoms = 3.011 × 1024
We know that 12g (atomic mass of carbon) of carbon contains 6.022 × 1023 carbon atoms.
Mass of 1 atom of carbon = 12/6.022 × 1023 = 1.99 × 10-23
Hence, mass of 3.011 × 1024 carbon atoms = 3.011 × 1024 ×1.99 × 10-23 = 59.9g or 60g (approximately)
APPEARS IN
RELATED QUESTIONS
Write down the name of a compound represented by the following formula:
Al2(SO4)3
Calculate the number of molecules of sulphur (S8) present in 16 g of solid sulphur.
Define: Atomic number
One of the forms of a naturally occurring solid compound P is usually used for making the floors of houses. On adding a few drops of dilute hydrochloric acid to P, brisk effervescence are produced. When 50 g of reactant P was heated strongly, than 22 g of a gas Q and 28 g of a solid R were produced as products. Gas Q is the same which produced brisk effervescence on adding dilute HCl to P. Gas Q is said to cause global warming whereas solid R is used for white-washing.
- What is (i) solid P (ii) gas Q, and (iii) solid R.
- What is the total mass of Q and R obtained from 50 g of P ?
- How does the total mass of Q and R formed compare with the mass of P taken ?
- What conclusion do you get from the comparison of masses of products and reactant ?
- Which law of chemical combination is illustrated by the example given in this problem ?
Molecular compounds are usually formed by the combination between :
Give one example of a triatomic molecule
Give one example of a polyatomic molecule.
State the main points of the contradiction of Dalton’s atomic theory by the Modern Atomic Theory.
Give a reason why –
Helium is considered monoatomic, but hydrogen a diatomic molecule.
Classify the following molecules as the molecules of element or compound
| 1. |  |
|
| 2. |  |
|
| 3. |  |
|
| 4. |  |
