Answer:
Isotopes
Explanation:
Isotopes are the same element with different masses because of the different number of neutrons. Also, the element doesn't change. If we change the protons, the element will change and then it won't be an isotope. Hope it helps!
1 mile = 1609.344 meters
1 hour = 3600 seconds 345.48 miles per hour x 1609.344
meters/mile x 1hour/3600seconds = 154.44 meter per second~~ANSWERR
Answer: norfenefrine
Explanation:
Depression in freezing point is given by:

= Depression in freezing point
i= vant hoff factor = 1 (for non electrolyte)
= freezing point constant = 
m= molality

Weight of solvent (ethanol)= 
Molar mass of unknown non electrolyte = M g/mol
Mass of unknown non electrolyte added = 82 mg = 0.082 g (1g=1000mg)


The molecular mass of norfenefrine
is near to 154 and thus the identity of the white powder is norfenefrine .
Answer:
(Z)-4-methyl-2-pentene
Explanation:
Hydrogenation is a syn addition. This implies that the hydrogen atoms add to the same face of the multiple bond.
Hence, if we have the alkyne, 4-methyl-2-pentyne which reacts with excess hydrogen in the presence of a platinum catalyst, we obtain (Z)-4-methyl-2-pentene since the hydrogen atoms add on the same side of the multiple bond.