Answer:
r u in high school this is hard
Explanation:
He has to use a different colored light at a higher frequency.
To solve this we use the equation,
M1V1 = M2V2
where M1 is the concentration
of the stock solution, V1 is the volume of the stock solution, M2 is the
concentration of the new solution and V2 is its volume.
M1V1 = M2V2
1% x V1 = 0.25% x 10 mL
V1 =2.5 mL
Therefore, you will need to have 2.5 mL of the 1% HCl solution and 7.5 mL of distilled water. In mixing the two liquids, you should remember that the order of mixing would be acid to water. So, you use a 10 mL volumetric flask . Put small amount of distilled water and add the 2.5 mL of HCl solution. Lastly, dilute with distilled water up to the 10 mL mark.
Lower the melting point
Explanation:
Salts helps to melt road by lowering the melting point. It acts as an impurity and generally, impurities low the melting point of substances.
Salts are used as an antifreeze.
- Water freezes at 0°C and forms ice/snow which can impede human and vehicular movement.
- When salt is added, it causes the depression of the freezing point by lowering it further.
- The freezing point is pegged back at -6°C.
- This way it takes more low temperature to freeze the water.
- The salt acts as an impurity and causes the depression of melting point and widening of the melting range.
learn more:
Matter brainly.com/question/10972073
#learnwithBrainly
1 mol = 6.023x10^23 number of molecules (Avogadro's number)
1 : 6.023x10^23
X : 4.91x10^22
(6.023x10^23)X = 4.91x10^22
X = 4.91x10^22/6.023x10^23
X = 0.082 Moles