Atomic mass of helium is 4.002642g/mol
(542000g)/(4.002642g/mol)*6.02*10^23 = 8.15*10^28 atoms
Answer: Root nodules are associations between bacteria and plant roots responsible for nitrogen fixation.
Explanation:
- As nitrogen present in atmosphere cannot be used by plants directly.
- Nitrogen present in atmosphere is converted into nitrogen compounds by bacteria which is present in root nodules of a plant.
- These compounds of nitrogen are then used by plants for various functions.
Answer:
iconic bonded unit
polyatomic ions can be covalently bonded
it has cations and anions
Answer:
Percent yield is 25%
Explanation:
Information given is
Actual yield is 25 g
But the yield should be 100 g
The percent yield is defined as the ratio of the actual yield and the predicted yield it means that out of the predicted yield what percentage of the actual yield is obtained
∴ Percent yield = (Actual yield ÷ Predicted yield) × 100
In case of the given problem the percent yield will be
(25÷100) × 100 = 25%
∴ Percent yield = 25%
a) (NH4)2SO4 --- 1 mole of it contains 2 moles of N, 8 moles of H, 1 mole of S, and 4 moles of O.
MM = (2 moles N x 14.0 g/mole) + (8 moles H x 1.01 g/mole) + (1 mole S x 32.1 g/mole) + (4 moles O x 16.0 g/mole) = 132 g/mole.
6.60 g (NH4)2SO4 x (1 mole (NH4)2SO4 / 132 g (NH4)2SO4) = 0.0500 moles (NH4)2SO4
b) The molar mass for Ca(OH)2 = 74.0 g/mole, calculated like (NH4)2SO4 above.
4.5 kg Ca(OH)2 x (1000 g / 1 kg) x (1 mole Ca(OH)2 / 74.0 g Ca(OH)2) = 60.8 moles Ca(OH)2
