Answer:
12.5 gm left
Explanation:
30 minutes is THREE half lives
1/2^3 = 1/8th would be left
100g * 1/8 = 12.5 gm
Answer:
20.2 kJ
Explanation:
Based on the information in the reaction, the amount of heat released per mole of Na₂O₂ (the molar enthalpy) is calculated as follows:
126 kJ / 2 mol = 63 kJ/mol Na₂O₂
The number of moles in 25.0g of Na₂O₂ must be calculated using the molecular weight of Na₂O₂ (77.978 g/mol):
(25.0 g)/(77.978 g/mol) = 0.32060 mol Na₂O₂
Thus, the heat released will be:
(63 kJ/mol)(0.32060 mol) = 20.2 kJ
Fluorine is an element with the highest electronegativity value.
Answer:
of acetic anhydride is needed
Explanation:
According to balanced equation, 1 mol of salicylic acid completely reacts with 1 mol of acetic anhydride
Number of moles = (mass)/(molar mass)
Molar mass of acetic anhydride = 102.09 g/mol
Molar mass of salicylic acid = 138.121 g/mol
So, 
of salicylic acid = 
of salicylic acid
Hence, of salicylic acid reacts completely with of acetic anhydride.
So, mass of acetic anhydride needed = 
=
False, because prokaryotes do not have a nucleus.
