Answer:
This is a conversion factor
Answer:
1·199 J
Explanation:
Given
Mass of water = 0·814 g = 0·814 × 
kg
Increase in temperature = 0·351 °C
Let the amount of heat added be Q J
Formula for heat added is
<h3>Q = m × s × ΔT</h3>
where Q is the amount of heat transferred
m is the mass
s is the heat capacity
ΔT is the change in temperature
Heat capacity of water = 4200 J/kg °C
Applying the formula for heat added
Q = 0·814 × × 4200 × 0·351 = 1·199 J
∴ Amount of heat added = 1·199 J
Answer:
0.92moles
Explanation:
Given reaction:
2Fe + 3Cl₂ → 2FeCl₃
Mass of FeCl₃ = 100g
Unknown:
Number of moles of Cl₂ needed = ?
Solution:
To solve this problem, we work from the known specie to the unknown.
From the mass of the FeCl₃ given, we can solve for the number of moles of the unknown.
- Number of moles of FeCl₃;
Number of moles = 
Molar mass of FeCl₃ = 56 + 3(35.5) = 162.5g/mol
Number of moles = 
= 0.62mole
From the reaction expression;
2 mole of FeCl₃ is produced from 3 moles of Cl₂
0.62 mole of FeCl₃ will be produced from 
= 0.92mole
The number of moles of Cl₂ = 0.92moles
At time t = 273.15 °C, the x-intercept occurs. According to Charles' law, an ideal gas's volume decreases as its temperature rises. At t = 273.15 °C, the graph's x-intercept, volume approaches zero.
<h3>Charles law experiment: what is it?</h3>
Describe the Charles Law experiment. Gases have a tendency to expand when heated, according to Charles' law (sometimes referred to as the law of volumes), an experimental gas law. The Kelvin temperature and the volume will be directly proportional when the pressure on a sample of the a dry gas is held constant, according to a current interpretation of Charles's law.
<h3>Which laws—Charles and Boyles—have similarities?</h3>
Boyle's law is formulated for systems with constant temperature, whereas Charles' law is formulated for systems with constant pressure.
<h3>To know more about Charles law visit:</h3>
brainly.com/question/16927784
#SPJ13
Answer:
12 mmilligrams of Po-218 was the mass of the original starting material
Explanation:
The half-life of a radioactive material is the time taken for half the amount ofnthe original material present in a radioactive material to decay or disintegrate.
After each half-life, half the original material present at the start remains.
For the radioactive polonium-218 having a half-life of 3.04 minutes, it means that if 1 g is the starting material, after 3.04 minutes, 1/2 g will be remaining; after, 6.08 minutes 1/2 of 1/2 which is 1/4 of the starting material will be remaining; and after 9.12 minutes, 1/2 of 1/4 = 1/8 g will be remaining.
From the question, number of half-lives undergone after 9.12 minutes = 9.12/3.04 = 3 half-lives.
After 3 half-lives, 1/8 of the original material is remaining.
1/8 = 1.50 mg
The original mass of the sample at the start = 1.50 mg × 8 = 12 mg
Therefore, 12 milligrams of Po-218 was the mass of the original starting material.
