How does the density of warm water and cold water compare?
2 answers:
Answer: Option (c) is the correct answer.
Explanation:
Density is defined as mass present in per unit volume.
Mathematically, Density =
Since, density is directly proportional to mass. So, more is the mass that is, more is the number of molecules closer to each other more will be the density of substance.
So, when we cool water then decrease in temperature causes the molecules to slow down. As a result, they come closer to each other due to which there occurs increase in mass of the water. Hence, density of cold water increases.
Whereas when water is warm then molecules have more kinetic energy. So, they move away from each other due to more number of collisions. Hence, there will decrease in density of warm water.
Thus, we can conclude that cold water is denser than warm water.
You might be interested in
Answer:
0.675 atm
513 Torr
Explanation:
Given is that, the atmospheric pressure on the surface of Venus is
6.84 X 10⁴ Pa.
1 atm (atmospheric pressure) is equal to 101325 pascal (Pa).
To convert divide the pressure value by 101325.
Pressure in atm =
= 0.675055 atm
Rounding it off to 3 significant digits: 0.675 atm
Now, one Torr is 133.322 Pa. For conversion, divide the pressure value by 133.322.
Pressure in Torr =
=513.04219 Torr
Rounding it off to 3 significant digits: 513 Torr
Answer:
6,97x10⁻³ gallons
Explanation:
pH is defined as:
pH = -log [H⁺]
Thus, you need to have, in the end:
10⁻⁷ = [H⁺]
And you have, in the first:
= [H⁺]
The volume of swimming pool is:
700'000 galllons × = 2649787 L
Thus, the moles of H⁺ in the first and in the end are:
First:
× 2649787L = 1,24x10⁻³ moles
End:
× 2649787L = 0,265 moles
Thus, the moles of H⁺ you need to add are:
0,265 - 1,24x10⁻³ = <em>0,26376 moles</em>
These moles comes from 10M HCl, thus, the volume in gallons you need to add are:
=
<em>6,97x10⁻³ gallons</em>
<em></em>
I hope it helps!
Answer:
1.346 v
Explanation:
1) Fist of all we need to calculate the standard cell potential, one should look up the reduction potentials for the species envolved:
(oxidation) →
E°=0.337 v
(reduction) →
E°=1.679 v
(overall) +8H^{+}_{(aq)}→
E°=1.342 v
2) Nernst Equation
Knowing the standard potential, one calculates the nonstandard potential using the Nernst Equation:
Where 'R' is the molar gas constant, 'T' is the kelvin temperature, 'n' is the number of electrons involved in the reaction and 'F' is the faraday constant.
The problem gives the [red]=0.66M and [ox]=1.69M, just apply to the Nernst Equation to give
E=1.346