Explanation:
No of mass = no of moles × molar mass
=2.55 × 18 g
= 45.9 g
Answer:
The given compound cannot be cocaine.
Explanation:
The chemist can comment on the nature of compound being cocaine or not from the depression in freezing point.
Depression in freezing point of is related to molality as:
Depression in freezing point = Kf X molality
Where
Kf = cryoscopic constant = 4.90°C/m
depression in freezing point = normal freezing point - freezing point of solution
depression in freezing point = 5.5-3.9 = 1.6°C
1.6°C = 4.90 X molality

we know that:

therefore
moles = 0.327X0.008 = 0.00261 mol


The molar mass of cocaine is 303.353
So the given compound cannot be cocaine.
Answer:
Balancing chemical equation means making a number of atoms or molecules equal on both sides. In other words, this means that the number of atoms and molecules of each reacting element needs to be the same as the number of atoms and molecules of those elements in the product.
Our reaction is:
AlBr3 + K2SO4 -> KBr + Al2(SO4)3
and we need to balance it.
Since there are 3 molecules of SO4 in the product we need to put 3 before the reactant K2SO4. There are also 2 atoms of Al in the product, so we need to put 2 in front AlBr3. Now we have 6 atoms of K and Br on the left side, so we need to put 6 in front of KBr in the product.
So, our balanced equation will look like this:
2AlBr3 + 3K2SO4 -> 6KBr + Al2(SO4)3
Answer:
see calculations in explanation
Explanation:
percent = part/total x 100%
part = ∑ atomic mass of element
- hydrogen = 1.008 amu (atomic mass units)
- carbon = 12.011 amu
- nitrogen = 14.007 amu
total = ∑ molecular mass of compound
= H amu + C amu + Namu
= 1.008 amu + 12.011 amu + 14.007 amu
= 27.026 amu
%H = (1.008amu/27.026amu)100% = 3.730%
%C = (12.011amu/27.026amu)100% = 44.442%
%N = (14.007amu/27.026amu)100% = 51.827%
Check results ∑%values = 100%
3.730% + 44.442% + 51.827% = 99.999% ≅ 100%
Answer:
Increasing the concentration of the reagents makes the collision between two molecules of the reagents more likely, thereby increasing the probability that the reaction will occur between these reagents.
As for the relationship between concentration and volume, density also comes into play, a higher volume, lower molarity and also lower concentration.
The pressure when increasing could generate a closer approach between the particles, therefore generating an increase in the reaction speed.
Pressure and volume are related but inversely proportional, therefore if the volume increases the pressure decreases and so on.
the reaction rate increases as the contact surface area increases. This is due to the fact that more solid particles are exposed and can be reached by reactant molecules.
A perfect reaction where the collision is promoted and the reaction speed advances is with the presence of a solvent, with an increase in pressure and a decrease in volume, with an increase in the exposure of the surface, with the presence of a catalyst, with increasing temperature and with increasing entrance
Explanation:
The reaction rate is defined as the amount of substance that is transformed into a certain reaction per unit of volume and time. For example, the oxidation of iron under atmospheric conditions is a slow reaction that can take many years but over time it is oxidized sooner or later by the oxygenation of its surface layer, but the combustion of butane in a fire is a reaction that happens in fractions of seconds, giving rise to an exothermic reaction with products such as CO2 and H2O