A.) half - life of a radioactive substance is defined as the time during which concentration of the substance becomes half the initial value.
Reaction Rate is the rate at which a substance undergoes a chemical change.
<u>Answer:</u> The molality of magnesium chloride is 1.58 m
<u>Explanation:</u>
To calculate the molality of solution, we use the equation:

Where,
= Given mass of solute (magnesium chloride) = 75.0
= Molar mass of solute (magnesium chloride) = 95.21 g/mol
= Mass of solvent = 500.0 g
Putting values in above equation, we get:

Hence, the molality of magnesium chloride is 1.58 m
Answer:224
Explanation:
We should answer it with Stoichiometry
We say: 20 g H2× (1 mol/ 2g)× ( 22.4 lit/ 1 mol) = 224
Means: we have 20 grams and every 2g H2, equals to 1 mol of it and every 1 mol of H2, equals to 22.4 lit( because of STP)
hope you got this:)
In the data, 0.20 ppm is an outlier and this can be rejected if there is a 95% confidence level.
<h3>What is an outlier?</h3>
When analyzing data an outlier is a value that is abnormal or too different from other data. In the case presented 0.20 can be tagged as an outlier because other values such as 0.11, 0.12, 0.13, and 0.14 are similar while 0.20 is outside this range.
<h3>Should this piece of data be rejected?</h3>
The general rule is that if there is a 95% of confidence or higher you can reject an outlier, knowing the other data occurs 95% of the time, and therefore the outlier is improbable.
Based on this, you can reject an outlier if the confidence level is 95%.
Learn more about outlier in: brainly.com/question/9933184