Answer:
270 Joules
Explanation:
The specific heat capacity equation will be used for this question i.e.
Q = m. c. ΔT
Where; Q = Amount of heat
m = mass of substance
C = specific heat capacity of
substance
ΔT = change in temperature
(Final temp - initial temp)
However, for this unknown metal, we need to find the specific heat first by saying; C = Q / mΔT
Q= 135J, C=?, m= 10g, ΔT = (40-25 = 15°C)
C = 135 / 15 × 10
C = 135/150
C = 0.9 J/g°C
If the specific heat capacity of the unknown metal is 0.9 J/g°C, then at a mass of 20.0g, and a ΔT of 15°C, the amount of heat needed is:
Q = m. c. ΔT
Q = 20 × 0.9 × (40-25)
Q = 18 × 15
Q = 270J
270 Joules of heat is needed to increase the temperature of 20g of the metal from 25 - 40°C
Answer:
5.2 x 10⁻⁴ M.
Explanation:
- The relationship between gas pressure and the concentration of dissolved gas is given by Henry’s law:
<em>P = kC</em>
where P is the partial pressure of the gaseous solute above the solution.
k is a constant (Henry’s constant).
C is the concentration of the dissolved gas.
- At two different pressures, there is two different concentrations of dissolved gases and is expressed in a relation as:
<em>P₁C₂ = P₂C₁,</em>
P₁ = 1.0 atm, C₁ = 6.8 x 10⁻⁴ mol/L.
P₂ = 0.76 atm, C₂ = ??? mol/L.
<em>∴ C₂ = (P₂C₁)/P₁ =</em> (0.76 atm)(6.8 x 10⁻⁴ mol/L)/(1.0 atm) = <em>5.168 x 10⁻⁴ mol/L ≅ 5.2 x 10⁻⁴ M.</em>
Answer: Cardiovascular System
Explanation:
This involves your heart, blood, veins, and arteries
We can use the dilution formula to find the volume of the diluted solution to be prepared
c1v1 = c2v2
Where c1 is concentration and v1 is volume of the concentrated solution
And c2 is concentration and v2 is volume of the diluted solution to be prepared
Substituting the values in the equation
15 M x 25 mL = 3 M x v2
v2 = 125 mL
The 25 mL concentrated solution should be diluted with distilled water upto 125 mL to make a 3 M solution