Answer:
b. 50ppm of Pb
c. 2x10⁻⁴M
j. no
Explanation:
The diluted sample has a concentration of 0.5 ppm of Pb. The sample was diluted from 1mL to 100mL. That means the dilution factor is:
100mL / 1mL = 100
That means, the sample was diluted 100 times from its original concentration.
As diluted sample has a concentration of 0.5ppm, the undiluted sample has a concentration of
0.5ppm×100 = <em>50ppm of Pb</em>
1 ppm means 1x10⁻⁴ % by mass, 50 ppm are 50x10⁻⁴ % by mass
As molar mass of Pb is 207g/mol, molarity of 0.050g / L a(50 ppm) are:
0.050gₓ (1mol / 207g) / 1L = <em>2x10⁻⁴M</em>
<em></em>
Based on EPA regulation, the maximum concentration of Lead in drinking water must be 0.015ppm. That means this water <em>is not safe to drink</em>
Fat and soap are different substances. <span>One reason is that they have a different malleability. The Soap is very hard and sturdy. The fat is soft. Also, soap and fat are different because they had different smells. The soap had a refreshing smell and a soapy one and the fat smelled rubbery like Play-doh. Another reason why fat and soap are different substances is that they don’t dissolve the same in water and oil. Soap is soluble in water and shortening is not soluble in water. Soap is not soluble in oil and shortening is soluble in oil. In the water shortening did not become cloudy but soap did. When placed in oil, the shortening disappeared completely, while soap did not change at all.The melting point of the fat was 57.6 we could not find the melting point of the soap. The soaps melting point is higher than the water's boiling point. A property is something that describes an object and does not change. For example, the soap is white, where the fat is off white. Color is a property. Fat and soap are also different because they have different densities. The soap sank but the fat floated. The density of fat is about .88 g/ml and the density of soap is about 1.18 g/ml. </span><span>Fat and soap are not the same substances one reason is they have different properties.Malleability, hardness, solubility, melting point,color, and density are all properties. </span>A property is a characteristic of a substance that does not change. Different substances have different properties.<span> If they had the same properties, they would be the same substance, but, since they don’t, they are different substances.
Hope this helps :D</span>
Answer:
B
Explanation:
The tendency of a liquid to convert to vapour increases smoothly with increasing temperature. Vapour pressure shows the tendency of a liquid to convert to vapour. Increase In vapour pressure shows an increased tendency to convert to vapour. The higher the temperature, the higher the vapour pressure.
A simple magnetic compass can be used
