Volume of 1 mole of any gas under STP = 22.4 L,
so
0.15 mol*22.4 L/1 mol = 3.36 L of H2
Answer:
6 days
Explanation:
The following data were obtained from the question:
Original amount (N₀) = 100 mg
Amount remaining (N) = 6. 25 mg
Time (t) = 24 days
Half life (t½) =?
Next, we shall determine the decay constant. This can be obtained as follow:
Original amount (N₀) = 100 mg
Amount remaining (N) = 6. 25 mg
Time (t) = 24 days
Decay constant (K) =?
Log (N₀/N) = kt / 2.303
Log (100/6.25) = k × 24 / 2.303
Log 16 = k × 24 / 2.303
1.2041 = k × 24 / 2.303
Cross multiply
k × 24 = 1.2041 × 2.303
Divide both side by 24
K = (1.2041 × 2.303) / 24
K = 0.1155 /day
Finally, we shall determine the half-life of the isotope as follow:
Decay constant (K) = 0.1155 /day
Half life (t½) =?
t½ = 0.693 / K
t½ = 0.693 / 0.1155
t½ = 6 days
Therefore, the half-life of the isotope is 6 days
Answer:
P₂ = 2.88 atm
Explanation:
Given data:
Initial volume of gas = 1.8 L
Final volume = 750 mL
Initial pressure = 17.5 Psi
Final pressure = ?
Solution:
We will convert the units first:
Initial pressure = 17.5 /14.696 = 1.2 atm
Final volume = 750 mL ×1L/1000L = 0.75 L
The given problem will be solved through the Boly's law,
"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"
Mathematical expression:
P₁V₁ = P₂V₂
P₁ = Initial pressure
V₁ = initial volume
P₂ = final pressure
V₂ = final volume
Now we will put the values in formula,
P₁V₁ = P₂V₂
1.2 atm × 1.8 L = P₂ ×0.75 L
P₂ = 2.16 atm. L/ 0.75 L
P₂ = 2.88 atm
Heating the reaction flask on a hot plate is an example of supplying activation energy to begin a reaction.
Explanation:
<u>Definition:</u>
Activation energy is defined as the minimum amount of energy required to start a particular chemical reaction.
For example: When hydrogen and oxygen are mixed together it does not immediately start the reaction to form water. So, to start the reaction a small electric spark is provided or it is heated to provide some energy. This energy causes the molecules of hydrogen and water to react, thus producing even more molecules to react and finally water is formed.
Here the electric spark or the heat provided is the activation energy.
Answer:
IF the fruit juice contains a high level of vitamin C, THEN the preventative effectiveness against common cold increases.
Explanation:
The hypothesis is a testable explanation of a scientific investigation. It aims at predicting the outcome of the experiment. One feature of the hypothesis is that it must be testable. The hypothesis is usually written in an "IF, THEN" format.
This question is regarding an experiment to test the amount of vitamin C in fruit juice. The vitamin C is thought to be an effective preventative against common cold. Hence, the hypothesis connects the effect on common cold (dependent variable) with the amount of vitamin C (independent variable). The hypothesis can be written as:
IF the fruit juice contains a high level of vitamin C, THEN the preventative effectiveness against common cold increases.
