Answer:
<h2>0.5 moles</h2>
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
We have the final answer as
<h3>0.5 moles</h3>
Hope this helps you
Answer:
The molar mass in g/mol is 121.4 g/m
Explanation:
Let's apply the Ideal Gases Law to solve this:
P . V = n . R. T
V = 125 mL → 0.125L
P = 754 Torr
760 Torr ___ 1 atm
754 Torr ____ (754 / 760) = 0.992 atm
Moles = Mass / Molar mass
0.992 atm . 0.125L = (0.495 g / MM) . 0.082 . 371K
(0.992 atm . 0.125L) / (0.082 . 371K) = (0.495 g / MM)
4.07x10⁻³ mol = 0.495 g / MM
MM = 0.495 g / 4.07x10⁻³ mol → 121.4 g/m
If you mean what group of elements react the most, the answer is the alkali metals and the halogens because they both only either need to gain or lose one electron. If you mean the most reactive element, it would be fluorine because it has the most electronegativity.
Answer:
a) T
b) T
c) F
d) F
e) T
f) T
g) T
h) F
I) F
j) F
k) F
l) F
Explanation:
The w/v concentration is obtained from, mass/volume. Hence;
%w/v= 50/1000= 5%
In the %w/w we have;
25g/100 g = 25% w/w
In combustion reaction, energy is given out hence it is exothermic.
Neutralization reaction yields a salt and water
% by mass of carbon is obtained from;
8× 12/114 × 100 = 84.1%
All the ionic substances mentioned have very low solubility in water.
One mole of a substance contains the Avogadro's number of each atom in the compound.
There are two iron atoms so one mole contains 2× 55.85 g of iron.
Some sulphates such as BaSO4 are insoluble in water.
Halides are soluble in water hence NaI is soluble in water.
The equation does not balance with the given coefficients because the number of atoms of each element on both sides differ.
The equation represents a decomposition of calcium carbonate as written.
