They all have the same number of electrons in the electron cloud.
The answer gonna be: 1/2^n = 1/2^4 = 0.0625
So, 6.25% sample has not decayed yet!!!
Answer:
is the change in enthalpy associated with the combustion of 530 g of methane.
Explanation:
Mass of methane burnt = 530 g
Moles of methane burnt = 
Energy released on combustion of 1 mole of methane = -890.8 kJ/mol
Energy released on combustion of 33.125 moles of methane :
is the change in enthalpy associated with the combustion of 530 g of methane.
Answer;
Molar mass of water is 18.02 g/mol
Explanation;
-Molar mass of a compound is determined by adding the relative atomic mass of each atom present in the compound. Molar mass of one mole of a compound, it is the weight in grams of 6.02 × 1023 atoms or molecules.
-Therefore; to calculate the molar mass of Water (H2O); we first know the RAM of hydrogen and oxygen which are; H=1.01 and O= 16.00
Since there is two atom of hydrogen and one atom of oxygen in water;
Then; the Molar mass of water will be; 2×1.01 + 1 ×16 = 18.02 g/mol
