Answer:
2gcm⁻³
Explanation:
Given parameters:
Mass of the object = 20g
Volume = 10mL
Unknown:
Density of the object = ?
Solution:
Density of a body is its mass per unit volume;
Density =
We need to convert mL to cm³ for the volume
1mL = 1cm³;
10mL is therefore, 10cm³
So;
Density = = 2gcm⁻³
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