This question refers to significant figures. The reason we follow significant figure rules when performing calculations in science is that a calculated answer (which is an extrapolation of a manipulation of measurements) can only be as precise as the least precise measurement recorded. This means if you record measurements to a certain precision, the calculated answer at the most can only match the recorded level of precision as to balance the level of confidence in accuracy before and after calculations.
<u>Answer:</u> The correct answer is Option B.
<u>Explanation:</u>
Precipitate is defined as insoluble solid substance that emerges when two different aqueous solutions are mixed together. It usually settles down at the bottom of the solution after sometime.
For the given chemical equation:

The products formed in the reaction are calcium carbonate and potassium chloride. Out of the two products, one of them is insoluble which is calcium carbonate. Thus, it is considered as a precipitate.
Hence, the correct answer is Option B.
Answer:
a solution of acetic acid and sodium acetate
Explanation:
A buffer solution is defined as a solution which resist a change in pH when small quantity of a strong acid or a strong base are added. A buffer solution is made up of mixture of a weak acid and its conjugate base or a mixture of a weak base and its conjugate acid.
Acetic acid is the only option because it is a weak acid with a corresponding conjugate base, acetate. Unlike a solution of sulfuric acid and sodium sulfate in which the sulfuric acid is a strong acid which doesn’t qualify it to be a buffer solution. The remaining options have different acid compounds paired together which makes them invalid too.
Answer:
1.88 x 10^5
Explanation:
You have to round because all of the numbers in 187515.4207 are significant
Round to: 188000
Put in scientific notation:
1.88 x 10^5
Answer:
The answer is
<h2>1.74 g/mL</h2>
Explanation:
The density of a substance can be found by using the formula

From the question
mass of magnesium = 11.81 g
volume = 6.80 mL
The density of the metal is

We have the final answer as
<h3>1.74 g/mL</h3>
Hope this helps you