Answer:
Explanation:
Your strategy here will be to
use the chemical formula of carbon dioxide to find the number of molecules of
CO
2
that would contain that many atoms of oxygen
use Avogadro's constant to convert the number of molecules to moles of carbon dioxide
use the molar mass of carbon dioxide to convert the moles to grams
So, you know that one molecule of carbon dioxide contains
one atom of carbon,
1
×
C
two atoms of oxygen,
2
×
O
This means that the given number of atoms of oxygen would correspond to
4.8
⋅
10
22
atoms O
⋅
1 molecule CO
2
2
atoms O
=
2.4
⋅
10
22
molecules CO
2
Now, one mole of any molecular substance contains exactly
6.022
⋅
10
22
molecules of that substance -- this is known as Avogadro's constant.
In your case, the sample of carbon dioxide molecules contains
2.4
⋅
10
22
molecules CO
2
⋅
1 mole CO
2
6.022
⋅
10
23
molecules CO
2
=
0.03985 moles CO
2
Finally, carbon dioxide has a molar mass of
44.01 g mol
−
1
, which means that your sample will have a mass of
0.03985
moles CO
2
⋅
44.01 g
1
mole CO
2
=
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
∣
∣
a
a
1.8 g
a
a
∣
∣
−−−−−−−−−
The answer is rounded to two sig figs, the number of sig figs you have for the number of atoms of oxygen present in the sample.
Answer:-
Gravitational forces exerted on any two <em><u>bodies</u></em> in the universe
Hope it helps you...
✅
Volume of tank =
(given)
Since,
So,

For
:

The significant rule for multiplication, states that the number of significant figures in the answer obtained by multiplication is determined by the value with the lowest number of significant digits.
Since, the minimum number of decimal places in the above multiplication operation is 1 so, the final result must be upto 1 decimal place only.

Hence, volume in
is 243.5.
Explanations:
<u>Question</u> <u>1:</u> Lithium in 20.00+ g is C. or D., but 25.00+ g is D. which means this is the correct option.
I am unsure of <u>Question</u> <u>2</u>. I don't think it is mole though.
<u>Question</u> <u>3:</u> Boron in 25.00-30.00 g is B. or D., but 25.00 g would be C.
<u>Question</u> <u>4:</u> 2.393 x 1024 atoms of Oxygen is 63.58 mole O. I don't know for sure, but I think this is correct.
<u><em>I am NOT professional. There is a chance I am incorrect. Please reply to me if I've made a mistake.</em></u>
Answer: Energy of reactants = 30, Energy of products = 10
Exothermic
Activation energy for forward reaction is 10.
Explanation:
Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and
for the reaction comes out to be negative.
Energy of reactants = 30
Energy of products = 10
Thus as energy of the product < energy of the reactant, the reaction is exothermic.
Activation energy
is the extra energy that must be supplied to reactants in order to cross the energy barrier and thus convert to products.
for forward reaction is (40-30) = 10.