X=240 g NaCl salt dissolves in solution.
Example: If we add 68 g sugar and 272 g water to 160 g solution having concentration 20 %, find final concentration of this solution.
Solution:
Mass of solution is 160 g before addition sugar and water.
100 g solution includes 20 g sugar
160 g solution includes X g sugar
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X=32 g sugar
Mass of solute after addition=32 + 68=100 g sugar
Mass of solution after addition=272 +68 + 160=500 g
500 g solution includes 100 g sugar
100 g solution includes X g sugar
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X= 20 % is concentration of final solution.
In a way, all of the answers could be argued for (for example: in the first option: if the scientists' opinions are understood to be "informed understanding of the causes of events"), but one of the options is the best:
Scientific laws describe specific relationships in nature without offering
an explanation.
The reason why I think this is true is that many laws are phased too short and too concise to provide comprehensive explanations, instead they describe the relationships that must hold.
One of the options is pplain false:
Scientific laws explain why natural events occur. -"Scientific laws were theories that have been tested, proven, and adopted as laws." - since they are not adopted as laws.
It’s the second won the air layer one
Answer:
Number 1 is false
Explanation:
1.- Charged molecules are insoluble in water. The statement is false, charged molecules are soluble in water and this is the main characteristic of charged molecules.
2.- Hydrophobic molecules tend to be nonpolar and hydrophilic molecules tend to be polar. This is true, hydrophobic molecules are non polar and hydrophilic molecules are polar.
3.- Gasoline has partial positive and negative charges which allows it to dissolve in water. This is true, gasoline is soluble in water.
4.- NH3 dissolves in water because its molecules form hydrogen bonds with water. This is true, NH3 interact with water because they can form hydrogen bonds.
5.- Hydrophobic molecules prefer to interact with each other in an aqueous solution. Absolutely true, hydrophobic molecules interact among them and they isolate from the environment.
