<span>The correct answer is (C) 0.2 mole MgCl2.
according to Van't Hoff factor rule which is the ratio between the actual
concentration of the particles produced when the substance dissolved and
the concentration of the substance as measured from its mass, so here 0.2
mole MgCl2 is the higher van't Hoff factor as it has more ions than other
choices and the higher concentration.
and when the boiling point formula is delta Tb = Kb * m * i.
when delta Tb is the change in boiling point.
and Kb is molal boiling point constant
and m is the molality of the solution
and i is Van't Hoff factor.
so we can see the relationship between i and delta Tb, the greater Van't Hoff factor the higher the boiling point. so 0.2 MgCl2 is the higher boiling point as it is the greater van't Hoff factor.</span>
The correct answers are options C, that is, silver tarnishes and becomes black when exposed to oxygen, and option E, that is, diesel fuel burns when it is heated.
Chemical changes refer to the modifications in which the chemistry at molecular level is modified as the initial substance gets transformed into a new and different final substance. This change occurs with the dissociation of old bond and production of new bonds respectively.
Silver gets tarnished and becomes black when exposed to oxygen. This refers to a chemical change as silver a white and lustrous substance gets transformed into a tarnish black final substance. However, silver does not easily react with oxygen at usual circumstances. It easily reacts with sulfur comprising components in the air and generates black compound as Ag₂S.
Burning of diesel fuel when it is heated. Diesel refers to a mixture of hydrocarbons varying approximately from C₁₀H₂₀ to C₁₅H₂₈. When these hydrocarbons get burnt they generate novel substances, that is, carbon dioxide and water. Hence, it is also a chemical reaction.
Answer:
Density = 11.4 g/cm³
Explanation:
Given data:
Density of lead = ?
Height of lead bar = 0.500 cm
Width of lead bar = 1.55 cm
Length of lead bar = 25.00 cm
Mass of lead bar = 220.9 g
Solution:
Density = mass/ volume
Volume of bar = length × width × height
Volume of bar = 25.00 cm × 1.55 cm × 0.500 cm
Volume of bar = 19.4 cm³
Density of bar:
Density = 220.9 g/ 19.4 cm³
Density = 11.4 g/cm³
Answer:
if speed or direction changes then there is a change in velocity which is acceleration. Hope this helps!
Explanation:
