Answer:
2 litres of pure alcohol will be added to make the overall concentration of 9 litres of mixture as 30%.
Explanation:
Suppose x is the number of litres added to the 10% mixture than the quantity of new mixture is given as below
litres
litres
Also the quantity of alcohol is given as
Now the equation is as
So 2 litres of pure alcohol will be added to make the overall concentration of 9 litres of mixture as 30%.
The atmosphere contains the air we breathe
Answer:
A solution of acetic acid that is 60.0% HC₂H₃O₂ (by mass) indicates that it contains 60.0 g of acetic acid and 100.0 g of water.
Explanation:
A percentage is a way of expressing an amount as a fraction of 100. The mass percentage corresponds to physical units of the solutions and they allow to establish more precisely the concentration of the solutions and express them in terms of percentages.
Mass percentage indicates the amount in grams of solute per 100 grams of solution.
So a solution of acetic acid that is 60.0% HC₂H₃O₂ (by mass) indicates that it contains 60.0 g of acetic acid and 100.0 g of water.
Answer:
f = 80 flutter/ second
T= 0.0125 sec
Explanation:
Given data:
Fluttering of wings = 4800 time per minute
Frequency of wings = ?
Period for one wing in sec = ?
Solution:
There are 60 seconds in one minute, thus frequency of wings
4800/60 = 80 flutter per second
Period:
T = 1/f
T = 1/80
T= 0.0125 sec
Answer:
It gives the same result when an experiment is repeated.
Explanation:
Below are the possible answers to the question:
<em>It is biased.
</em>
<em>It cannot be verified.
</em>
<em>It cannot add new evidence to existing evidence.
</em>
<em>It gives the same result when an experiment is repeated.</em>
<em />
<em>The correct answer would be that </em><em>it gives the same result when an experiment is repeated.</em>
If a reaction is conducted in chemistry and certain results are obtained, once a detailed procedure of the experiment is known along with all the chemicals involved, such reaction/experiment can be repeated anywhere in the world and the same result would be obtained.
<u>The repeatability of experiments always makes the experiments to be reliable.</u> Hence, chemistry is reliable because it gives the same result without any variation when experiments are repeated under similar conditions.
