Actual yield over theoretical yield, then multiply by 100
Answer: 10ml
In this question, you are given the liquid medicine concentration (100mg/5ml) and the doses of the medicine that must be taken(200mg). You are asked how much ml of the drug needed. Then the calculation would be:
Volume of drug needed= doses of the drug / drug concentration
Volume of drug needed= 200mg / (100mg/5ml)= 10ml
The researcher may first weight the beaker with water and then start to heat the water to a constant temperature, for example 30 °C and then start adding salt and stirring. He should add salt slowly until solid salt starts to become visible and the solution starts becoming cloudy. When this happens, he should quickly weigh the beaker. The increase in mass is the mass of salt dissolved at that temperature.
The procedure is then repeated but at an increased temperature until 5-6 temperatures have been tested.
Answer:
Cooling a substance causes molecules to slow down and get slightly closer together, occupying a smaller volume that results in an increase in density. Hot water is less dense and will float on room-temperature water. <u>Cold water is more dense and will sink in room-temperature water.</u>
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