Answer:
1.004×10²²
Explanation:
The molar mass of carbon is 12 g/mol
which means that:
<u>1 mole of carbon atoms has a mass of 12 grams.</u>
Since, diamond is a allotrope of carbon.
Mass of 1.00-carat diamond in grams is:
1.00 carat = 0.200 g
<u>
Since, 1 mole of C contains 6.022×10²³ atoms of C</u>
So,
12 grams contains 6.022×10²³ atoms of C
1 gram contains 6.022×10²³/ 12 atoms of C
0.200 gram contains (6.022×10²³/ 12)×0.200 atoms of C
Thus,
<u>1 carat diamond contains 1.004×10²² atoms of C.</u>
6 is the fourth significant figures
if the number behind it is 5 or more then 5, you must add 1 to the number and ALL the number behind it will turn into 0
so that the answer is 42560
Explanation:
Moles of metal,
=
4.86
⋅
g
24.305
⋅
g
⋅
m
o
l
−
1
=
0.200
m
o
l
.
Moles of
H
C
l
=
100
⋅
c
m
−
3
×
2.00
⋅
m
o
l
⋅
d
m
−
3
=
0.200
m
o
l
Clearly, the acid is in deficiency ; i.e. it is the limiting reagent, because the equation above specifies that that 2 equiv of HCl are required for each equiv of metal.
So if
0.200
m
o
l
acid react, then (by the stoichiometry), 1/2 this quantity, i.e.
0.100
m
o
l
of dihydrogen will evolve.
So,
0.100
m
o
l
dihydrogen are evolved; this has a mass of
0.100
⋅
m
o
l
×
2.00
⋅
g
⋅
m
o
l
−
1
=
?
?
g
.
If 1 mol dihydrogen gas occupies
24.5
d
m
3
at room temperature and pressure, what will be the VOLUME of gas evolved?
Answer:
4.64 grams.
Explanation:
without stating a desired unit, stating the answer in any unit is acceptable. So you can use grams and the problem is done for you
Answer: The density of the material is 2.66 g/mL and it is likely this is made of Aluminum
Explanation:
The first step to know the material of the chunk of metal is to calculate its density. The general formula for density is P (density) = 
. Moreover, in this case, it is known the mass is 37.28 g, but the volume is not directly provided. However, we know the water in the graduated cylinder had a volume of 20.0 mL and this increased to 34.0 mL when the chunk of metal is added, this means the volume of the metal is 14 mL (34.0 mL - 20.0 mL = 14 mL). Now let's calculate the density:
This means the density of this metal is 2.66 g/mL, which can be rounded as 2. 7 g/mL, and according to the chart, this is the density of aluminum. Therefore, this material of this chunk is aluminum.
