Answer: option A. 2
Explanation: in the formula Sr3(PO4)2, the 2 behind (PO4) is affecting both P and O4. It means that we have P2 in the formula
<h3>
Answer:</h3>
200 mL
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Explanation:</h3>
Concept tested: Dilution formula
We are given;
- Concentration of stock solution as 1.00 M
- Volume of the stock solution as 50 mL
- Molarity of the dilute solution as 0.25 M
We are required to calculate the volume of diluted solution;
- The stock solution is the original solution before dilution while diluted solution is the solution after dilution.
- Using the dilution formula we can determine the volume of diluted solution;
M1V1 = M2V2
Rearranging the formula;
V2 = M1V1 ÷ M2
= (1.00 M × 50 mL) ÷ 0.25 M
= 200 mL
Therefore, a volume of 200mL of 0.25 M solution could be made from the stock solution.
Answer:
It makes the pasta to get hot faster and boil quicker.
Explanation:
Adding salt to water actually raises the boiling point of the water, due to a phenomenon called boiling point elevation. Essentially, adding any non-volatile solute such as salt to a liquid causes a decrease in the liquid’s vapour pressure. A liquid boils when the vapour pressure above it equals atmospheric pressure, so a lower vapour pressure means you need a higher temperature to boil the water. The reason salt makes water boil faster has to do with specific heat capacities, or the energy it takes to raise the temperature of a substance. Salt ions dissolved in water bind to water molecules, holding them stable and making it harder for them to move around. As a result, the non-salt bound water molecules receive more of the energy provided by the stove, and therefore they get hot faster and boil quicker.
