Answer:
0.85M
Explanation:
Given parameters:
Mass of CuCl₂ = 400g
Volume of water = 3.5L
Unknown:
Molarity of the solution = ?
Solution:
Molarity is one of the ways of expressing the concentrations of a solution. It is defined as the number of moles per unit volume of a solvent.
Molarity = 
To find the number of moles of CuCl₂;
Number of moles = 
Molar mass of CuCl₂ = 63.6 + 2(35.5) = 134.6g/mol
Number of moles =
= 2.97moles
Molarity =
= 0.85M
Explanation:
First thing first, you mistyped the specific heat of water, which should be
c
water
=
4.18
J
g
∘
C
Now, a substance's specific heat tells you how much heat is required to increase the temperature of
1 g
of that substance by
1
∘
C
.
In the case of water, you would need
4.18 J
to increase the temperature of
1 g
of water by
1
∘
C
.
Notice that your sample of water has a mass of
1 g
as well, which means that the only factor that will determine the amount of heat needed will be the difference in temperature.
The equation that establishes a relationshop between heat and change in temperature looks like this
q
=
m
⋅
c
⋅
Δ
T
, where
q
- heat absorbed
c
- the specific heat of the substance, in your case of water
Δ
T
- the change in temperature, defined as the difference between the final temperature and the initial temperature
Plug in your values and solve for
q
to get
q
=
1.00
g
⋅
4.18
J
g
⋅
∘
C
⋅
(
83.7
−
26.5
)
∘
C
q
=
239.096 J
Rounded to three sig figs, the answer will be
q
=
239 J
Answer:
it would be redshift and cosmic background radiation
The pressure of the gas = 40 atm
<h3>Further explanation</h3>
Given
200 ml container
P = 2 atm
final volume = 10 ml
Required
Final pressure
Solution
Boyle's Law
At a fixed temperature, the gas volume is inversely proportional to the pressure applied

Input the value :
P₂ = P₁V₁/V₂
P₂ = 2 x 200 / 10
P₂ = 40 atm
I’m almost 100% sure it’s D