<span>Answer : The average atomic mass of rubidium = 85.468
Explanation: Given that 85Rb isotope has atomic mass of 84.912amu with abundance of 72.17%
therefore we get 84.912 x 0.7217 = 61.281
and 87Rb isotope has atomic mass of 86.909 with abundance of 27.83%
hence we get 86.909 x 0.2783 = 24.187
Thus we get 61.281 + 24.187 = 85.468 as the average atomic mass of Rubidium.</span>
Answer: C. enzyme
Explanation:
A catalyst is a substance which increases the rate of a reaction by taking the reaction through a different path which involves lower activation energy and thus more molecules can cross the energy barrier and convert to products.
The catalyst itself does not take part in the chemical reaction and is regenerated as such at the end.
Enzymes are proteins that reduce the activation energy of biological reaction. Enzymes increase the speed of a reaction and help it to run faster. Thus they are also called as bio catalysts.
Activated complex is the transition state which is very unstable and is formed during the course when reactants are converted to products.
Answer:
30.0g CaCl2
Explanation:
20.0g Ca(OH)2=0.270mol
(0.270mol)(111.0g/mol)=30.0g CaCl2
Q=mcT
125cal=(60.0g)(0.0920)(T-21)
[(125)/(60)(0.0920)]+21=T2
T2=43.6C
