Answer: Option (a) is the correct answer.
Explanation:
A chemical reaction where heat energy is absorbed by the reactant molecules is known as an endothermic reaction.For example, [tex]A + B + Heat \rightarrow AB[/tex]
The value of [tex]\Delta H[/tex] = +ve for an endothermic reaction.
In an endothermic reaction, heat being absorbed is utilized to break the bonds. Therefore, temperature of the system decreases.
On the other hand, a chemical reaction in which heat energy is released by the reactant molecules is known as an exothermic reaction. For example, [tex]C + D \rightarrow CD + Heat[/tex] is an exothermic reaction.Generally, there occurs an increase in temperature of the substance or system because of the evolution of heat during an exothermic reaction.
Thus, we can conclude that temperature increases indicates that an exothermic reaction has occurred.
Answer:
Temp increases
Explanation:
A 0.465 g sample of an unknown compound occupies 245 ml at 298 k and 1.22 atm. what is the molar mass of the unknown compound?
a.26.3 g/mol
b.33.9 g/mol
c.12.2 g/mol
d.38.0 g/mol
e.81.8 g/mol
Answer: Option (d) is the correct answer.
Explanation:
It is know that for an ideal gas PV = nRT
where P = pressure
V = volume
n = number of moles = [tex]\frac{mass}{molar mass}[/tex]
R = gas constant = 0.082 [tex]L atm K^{-1} mol^{-1}[/tex]
T = temperature
Therefore, put the given values in the formula above as follows.
PV = nRT
or, PV = [tex]\frac{mass}{molar mass}RT[/tex]
[tex]1.22 atm \times 0.245 L = \frac{0.465 g}{molar mass} \times 0.082 L atm K^{-1} mol^{-1} \times 298 K[/tex]
molar mass = 38.12 g/mol
= 38.0 g/mol (approx)
Therefore, we can conclude that the molar mass of the unknown compound is 38.0 g/mol.
To study Earth’s interior, geologists often rely on indirect methods, such as evidence from fossils. true or false
Answer:
the answer is false, the person that said true is incorect.
Explanation:
Answer: FALSE
Explanation:To study Earth’s interior, geologists often rely on indirect methods, such as evidence from fossils.