Answer:
5 g / ml
Explanation:
Convert the values given to g and ml
12.5 kg = 12500 g
2.5 L = 2500 ml
12500 g / 2500 ml = 5 g/ml
Answer: a. solution
Explanation:
A solution is a mixture which contains two or more than two types of components and they can be separated by physical means as well.Example: salt water
Molecule of an element is defined as the aggregate of atoms of similar elements. Example:
. Molecule of a compound is the aggregate of atoms of different elements in a fixed ratio by mass. Example: 
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. Example: 
A pure substance is a substance which contains definite composition of only one type of component. Hence, it cannot be separated by physical means. Example: Helium, water
Answer:
1.99 atm
Explanation:
Step 1:
Data obtained from the question. This include the following:
Initial pressure (P1) = 0.520 atm
Initial temperature (T1) = 26.2°C
Initial volume (V1) = 15.4L
Final temperature (T2) = constant = 26.2°C
Final volume (V2) = 4.02L
Final pressure (P2) =..?
Step 2:
Determination of the new pressure of the gas.
Since the temperature of the gas is constant, it means the gas is obeying Boyle's law. Thus, the new pressure of the gas can be obtained by applying the Boyle's law equation as shown below:
P1V1 = P2V2
0.520 x 15.4 = P2 x 4.02
Divide both side by 4.02
P2 = (0.520 x 15.4) / 4.02
P2 = 1.99 atm
Therefore, the new pressure of the gas is 1.99 atm