Answer:
The pair of arrows which represents the relationship of speeds of the two cars is;
The second option as shown in the attached drawing
Explanation:
The given parameters are;
The reading on the speedometer of one car = 20 m/s
The reading on the speedometer of the other car = 72 km/h = 20 m/s
The blue arrow = 20 m/s
Therefore, given that the speeds of both cars are equal (20 m/s = 72 km/h = 20 m/s), the pair of arrows that represent the relationship of speeds of the two cars is two equal length blue arrows which is the second option
The attached diagram showing the pair of arrows that represents the relationship of speeds of the two cars is drawn using Microsoft Visio.
Answer:
-5.51 kJ/mol
Explanation:
Step 1: Calculate the heat required to heat the water.
We use the following expression.
where,
- c: specific heat capacity
- m: mass
- ΔT: change in the temperature
The average density of water is 1 g/mL, so 75.0 mL ≅ 75.0 g.
Step 2: Calculate the heat released by the methane
According to the law of conservation of energy, the sum of the heat released by the combustion of methane (Qc) and the heat absorbed by the water (Qw) is zero
Qc + Qw = 0
Qc = -Qw = -22.0 kJ
Step 3: Calculate the molar heat of combustion of methane.
The molar mass of methane is 16.04 g/mol. We use this data to find the molar heat of combustion of methane, considering that 22.0 kJ are released by the combustion of 64.00 g of methane.
1000 g of feathers is the least dense