Answer:A mole is an arbitrary number of molecules in a single unit - refer to avogadro's number. Essentially, 1 mole is 6.022x10^23 molecules for ALL molecules or atoms, however one must remember that not all atoms/molecules are the same size, this is where mass comes into play. When you measure out 2 grams of carbon powder, there will be a lot more molecules present than if you weighed out 2 grams of thorium powder; this is because carbon is much smaller - kind of like a car filled with clowns, one given car can hold a lot of small clowns but only a few big ones; so the same volume is occupied but the amount of substance (clowns) varies on their own size. The arbitrary mass (relative to the hydrogen atom) for a molecule is the sum of its atomic components' atomic masses; e. g. C2H6's will have 2x12.00 (carbon) + 6x1.01 (hydrogen) = ~30 grams / mole.
Explanation:
The answer is a. temperature and pH can affect how the enzymes work
There are 1000 mg in 1 g
and there are 1000 g in 1 kg
Start by converting 1.34 mg to grams by dividing 1.34 mg by 1000 g = 0.00134 g
Then convert 0.00134 g to kg by dividing 0.00134 g by 1000 kg = 1.34×10^-6 kg OR 0.00000134 kg
There are 30 protons and 39 neutrons in the nucleus.
This must me the isotope of an element with an atomic mass close to 69 u.
The only candidates are Zn and Ga.
Zn has a zinc-69 isotope with mass 68.926 u.
Ga has a gallium -69 isotope with mass 68.925 u.
The isotope is probably

.
It has 30 protons and 39 neutrons.