Answer:
13.85 kJ/°C
-14.89 kJ/g
Explanation:
<em>At constant volume, the heat of combustion of a particular compound, compound A, is − 3039.0 kJ/mol. When 1.697 g of compound A (molar mass = 101.67 g/mol) is burned in a bomb calorimeter, the temperature of the calorimeter (including its contents) rose by 3.661 °C. What is the heat capacity (calorimeter constant) of the calorimeter? </em>
<em />
The heat of combustion of A is − 3039.0 kJ/mol and its molar mass is 101.67 g/mol. The heat released by the combustion of 1.697g of A is:
According to the law of conservation of energy, the sum of the heat released by the combustion and the heat absorbed by the bomb calorimeter is zero.
Qcomb + Qcal = 0
Qcal = -Qcomb = -(-50.72 kJ) = 50.72 kJ
The heat capacity (C) of the calorimeter can be calculated using the following expression.
Qcal = C . ΔT
where,
ΔT is the change in the temperature
Qcal = C . ΔT
50.72 kJ = C . 3.661 °C
C = 13.85 kJ/°C
<em>Suppose a 3.767 g sample of a second compound, compound B, is combusted in the same calorimeter, and the temperature rises from 23.23°C to 27.28 ∘ C. What is the heat of combustion per gram of compound B?</em>
Qcomb = -Qcal = -C . ΔT = - (13.85 kJ/°C) . (27.28°C - 23.23°C) = -56.09 kJ
The heat of combustion per gram of B is:
The molecule that could diffuse across the plasma membrane is methane (CH4).
<h3>What is diffusion?</h3>
Diffusion is the movement of fluids or substances from regions of high concentration toward regions of lower concentration.
The plasma membrane is the semipermeable membrane that surrounds the cytoplasm of a cell. The semipermeability means that it allows some molecules through but blocks other substances.
The semipermeable plasma membrane readily allows the passage of small hydrophobic and polar molecules.
Therefore, the molecule that could diffuse across the plasma membrane is methane (CH4).
Learn more about semipermeability at: brainly.com/question/1652796
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Answer:
average for silk =141"
average for cotton =96"
average for nylon = 70"
if you desire a slower falling parachute to protect the body from damage,
silk is the best
if you desire a faster falling parachute to escape enemy bullets,
nylon is the best
Explanation:
Homework 1
Problem Solving
1. Kelvin and Xavier were doing an investigation on parachutes. One of them suggested that the type of material the parachute was made from had an effect on how long it took to reach the ground. Their results are given in
the table below.
(a) Calculate the average time in seconds for each material.
Time taken for parachute to reach the ground (seconds)
MATERIAL
1st TRY
2nd TRY
3rd TRY
AVERAGE
Sik
144
140 average of 3 = 141
139
Cotton
98
96 average of 3 = 96
94
Nylon
72
68 average of 3 = 70
70
Answer:
Final temperature of the gas is 576 
.
Explanation:
As the amount of gas and pressure of the gas remains constant therefore in accordance with Charles's law:
where 
and 
are volume of gas at 
and 
temperature (in kelvin scale) respectively.
Here 
, 
and 
So 
849 K = (849-273) = 576
So final temperature of the gas is 576 .
Answer: The number of protons and the number of neutrons determine an element's mass number.
Explanation:
