Answer: D) 140g
Explanation: no. of moles of NaCl = molarity X volume in litres = 2 X 1.2 = 2.4, and molar mass or mass of 1 mole of NaCl = 58.44 g, so 2.4 moles NaCl = 140.256 g
Answer:
The final temperature of the solution is 44.8 °C
Explanation:
assuming no heat loss to the surroundings, all the heat of solution (due to the dissolving process) is absorbed by the same solution and therefore:
Q dis + Q sol = 0
Using tables , can be found that the heat of solution of CaCl2 at 25°C (≈24.7 °C) is q dis= -83.3 KJ/mol . And the molecular weight is
M = 1*40 g/mol + 2* 35.45 g/mol = 110.9 g/mol
Q dis = q dis * n = q dis * m/M = -83.3 KJ/mol * 13.1 g/110.9 gr/mol = -9.84 KJ
Qdis= -9.84 KJ
Also Qsol = ms * Cs * (T - Ti)
therefore
ms * Cs * (T - Ti) + Qdis = 0
T= Ti - Qdis * (ms * Cs )^-1 =24.7 °C - (-9.84 KJ/mol)/[(104 g + 13.1 g)* 4.18 J/g°C] *1000 J/KJ
T= 44.8 °C
Half-life is defined as the quantity to reduce to half of its initial value.
Explanation:
The term half-life is generally used in nuclear physics which describes how long a stable atom can survive a radioactive decay or how quickly an unstable stable atom can undergo radioactive decay. Half-life is a constant and does not have any units.
<u>The formula to calculate half-life:
</u>
N(t) = 
Here N(t) is the quantity which is “not decayed”.
is the “initial quantity” of the substance.
λ is the “decay constant”
Answer:
A. The gas molecules possess kinetic energy.
Explanation:
The characteristics of the Ideal gases are given by the Kinetic Theory of gases which are as follows:-
Gases consist of particles in constant, random motion. They continue in a straight line until they collide with something—usually each other or the walls of their container.
Particles are point masses with no volume. The particles are so small compared to the space between them, that we do not consider their size in ideal gases.
No molecular forces are at work. This means that there is no attraction or repulsion between the particles.
Gas pressure is due to the molecules colliding with the walls
<span>There are only three stereoisomers of 1,2-dimethylcyclopentane. As there are only two chiral carbons, so the maximum number of stereoisomers is 4, but two are the same meso-compound which means that there are only 3.</span>
