Answer:
a. -0.63 V
b. No
Explanation:
Step 1: Given data
- Standard reduction potential of the anode (E°red): -1.33 V
- Minimum standard cell potential (E°cell): 0.70 V
Step 2: Calculate the required standard reduction potential of the cathode
The galvanic cell must provide at least 0.70V of electrical power, that is:
E°cell > 0.70 V [1]
We can calculate the standard reduction potential of the cathode (E°cat) using the following expression.
E°cell = E°cat - E°an [2]
If we combine [1] and [2], we get,
E°cat - E°an > 0.70 V
E°cat > 0.70 V + E°an
E°cat > 0.70 V + (-1.33 V)
E°cat > -0.63 V
The minimum E°cat is -0.63 V and there is no maximum E°cat.
Answer:
False
Explanation:
Evaporation occurs when molecules in a liquid gain enough energy that they overcome attractions from other molecules and break away to become a gas. Adding energy increases the rate of evaporation.
Hope this helped!
The energy absorbed may be calculated using:
Q = mcΔT
Where Q is the energy absorbed, m is the mass of water, c is the specific heat capacity of the water and ΔT is the change is the temperature of the water. Substituting the values,
Q = (435)(4.18)(100-25)
Q = 136,372 J
The energy absorbed is 136.4 kJ
Evaporation and transpiration
Answer:
The sample of lead has a volume of 11.1 cm³
Explanation:
<u>Step 1:</u> Data given
x cm³ lead has a density of 11.3 g/cm³
it has the same mass as 330cm³ of a piece of redwood with density 0.38g/cm³
<u>Step 2</u>: Calculate mass of the piece of redwood
Density = mass/volume
mass = density * volume
Mass of the piece of redwood = 0.38 g/cm³ * 330cm³ = 125.4 grams
Since the sample of lead has the same mass, it also has a mass of 125.4 grams
<u>Step 3</u>: Calculate volume of the lead
Density = mass/ volume
Volume = mass/ density
Volume of lead = 125.4g / 11.3g/cm³ = 11.097 cm³≈11.1 cm³
The sample of lead has a volume of 11.1 cm³