Answer:
For these problems, we need to compare the theoretical yield that we'd get from performing stoichiometry to the actual yield stated in the problem. % yield is the actual yield/theoretical yield x 100%
Cu + 2 AgNO₠→ Cu(NOâ‚)â‚‚ + 2 Ag ==> each mole of copper yields two moles of silver
12.7-g Cu x ( 1 mol Cu /63.5-g Cu) x ( 2 mol Ag / 1 mol Cu) x (108-g Ag / 1 mol Ag) = 43.2-g Ag. This is the theoretical yield. Now, since we got 38.1-g Ag our % yield is:
38.1-g/43.2-g x 100% = 88.2%
Explanation:
It stays roughly the same size. Electrons have a barely imperceptible mass so the overall mass of the atom is changed very little.
Answer: The mass is 348.8g
Explanation:
We begin by using Avogadro's number to convert the number of molecules of Sodium Hydroxide to moles.
6.02 x 10∧23 molecules of NaOH -------> 1 mole of NaOH
∴ 5.25 x 10∧24 molecules of NaOH -------> 1/ 6.02 x 10∧23 x 5.25 x 10∧24 =
8.72moles.
Having found the number of moles, we then move from moles to gram by using the molar mass of NaOH (i.e the mass of 1 mole of NaOH).
1 mole of NaOH is equivalent to 40g (Molar Mass)
8.72 moles of NaOH would be equivalent to; 40/ 1 x 8.72 = 348.8g
The mass in 5.25 x 10∧24molecules of NaOH is 348.8g
Answer:
A
Explanation:
PV=nRT
PV/nT
V/T -> (1)/(300)=(x)/(150)
x=.420
Answer:
13) Carbon Dioxide and water
Explanation:
The fact is that during photosynthesis, Carbon Dioxide is needed by green plants to manufacture their food and water is also needed but also chloroplast which contained chlorophyll is also needed
hence, the options are somehow confusing
14) perhaps it should be all of the above
