Answer:

Explanation:
Considering,
Using ideal gas equation as:
where,
P is the pressure = 760 mmHg
V is the volume = 100.0 mL = 0.1 L
m is the mass of the gas = 0.193 g
M is the molar mass of the gas = ?
Temperature = 17 °C
The conversion of T( °C) to T(K) is shown below:
T(K) = T( °C) + 273.15
So,
T = (17 + 273.15) K = 290.15 K
R is Gas constant having value = 62.36367 L. mmHg/K. mol
Applying the values as:-
M = 45.95 g/mol
This mass corresponds to
. Hence, the gas must be
.
Answer:
B. using efficient light bulbs
<h2>Answer:</h2>
<u>The correct answer is Thermal Energy</u>
<h2>Explanation:</h2>
Thermal energy is the energy that comes from heat. This heat is generated by the movement of tiny particles within an object. The faster these particles move, the more heat is generated. Since the matchstick produces heat energy and heat is referred o thermal energy so it is the correct answer.
Answer: ![[OH^{-}]= 0.01M or 1.0\times 10^{-2}M](https://tex.z-dn.net/?f=%5BOH%5E%7B-%7D%5D%3D%200.01M%20or%201.0%5Ctimes%2010%5E%7B-2%7DM)
![[H^{+}]= 1.0\times 10^{-12}M](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D%3D%201.0%5Ctimes%2010%5E%7B-12%7DM)
pH = 12
pOH = 2
Explanation: Calcium hydroxide (
) is a strong base that dissociates completely.
Dissociation equation of Calcium hydroxide is :

1. Concentration of [OH-]
1 mol
produces 2 mol OH- ions.
The given solution is 0.005M
, then concentration of OH- would be twice the concentration of 
= 0.01M or 
2.Concentration of [H+]
Concentration of [H+] can be calculated by the formula: ![[H^{+}] = \frac{Kw}{[OH^{-}]}](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D%20%3D%20%5Cfrac%7BKw%7D%7B%5BOH%5E%7B-%7D%5D%7D)
kw = ionic product of water and its values is 
[OH-] = 0.01 M or 
![[H^{+}] = \frac{(1\times 10^{-14})}{[OH^{-}]}](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D%20%3D%20%5Cfrac%7B%281%5Ctimes%2010%5E%7B-14%7D%29%7D%7B%5BOH%5E%7B-%7D%5D%7D)
![[H^{+}] = \frac{(1\times 10^{-14})}{[0.01]}](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D%20%3D%20%5Cfrac%7B%281%5Ctimes%2010%5E%7B-14%7D%29%7D%7B%5B0.01%5D%7D)
![[H^{+}] = 1.0\times 10^{-12}M](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D%20%3D%201.0%5Ctimes%2010%5E%7B-12%7DM%20)
3. pH value
pH is calculated by the formula : ![pH = -log[H^{+}]](https://tex.z-dn.net/?f=pH%20%3D%20-log%5BH%5E%7B%2B%7D%5D)
![pH = -log[1.0\times 10^{-12}]](https://tex.z-dn.net/?f=pH%20%3D%20-log%5B1.0%5Ctimes%2010%5E%7B-12%7D%5D)
pH = 12
4. pOH value
pOH is calculated by the formula : pOH = 14 - pH
pOH = 14 - 12
pOH = 2
pOH can also be calculated by using a different formula which is :


pOH = 2.
Answer:
The given reaction is combustion reaction heat is also produced.
Explanation:
Chemical equation:
CH₄ + 2O₂ → CO₂ + 2H₂O
The given reaction is combustion of methane. When methane burn it produced water and carbon dioxide. Heat is also produced.
The given reaction followed the law of conservation of mass.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
Explanation:
This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
CH₄ + 2O₂ → CO₂ + 2H₂O
There are equal number of carbon hydrogen and oxygen atoms present on both side of equation. So it follow the law of conservation of mass.