Hello!
datos:
Molarity = 
ps: The ionization constant of the nitric acid is strong (100% ionized in water) or completely dissociates in water, so the pH will be:
![pH = - log\:[H_3O^+]](https://tex.z-dn.net/?f=%20pH%20%3D%20-%20log%5C%3A%5BH_3O%5E%2B%5D%20)
![pH = - log\:[2*10^{-4}]](https://tex.z-dn.net/?f=%20pH%20%3D%20-%20log%5C%3A%5B2%2A10%5E%7B-4%7D%5D%20)
Note:. The pH <7, then we have an acidic solution.
I Hope this helps, greetings ... DexteR!
Answer:
The correct answer is (b)
Explanation:
Charles law describes the behavior of gases when heated. Charles law states that the volume of a given mass of gas would increase as its Kelvin temperature increases provided the pressure is held constant. That is the volume of a given mass of gas is directly proportional to its Kelvin temperature at constant pressure
Given, half life of a certain radioactive element = 800 years.
Amount of substance remaining at time t = 12.5%
Lets consider the initial amount of the radioactive substance = 100%
Using the half life equation:
A = A₀(1/2)^t/t₁/₂
where A₀ is the amount of radioactive substance at time zero and A is the amount of radioactive substance at time t, and t₁/₂ is the half-life of the radioactive substance.
Plugging the given data into the half life equation we have,
12.5 = 100 . (1/2)^t/800
12.5/100 = (1/2)^t/800
0.125 = (0.5)^t/800
(0.5)^3 = (0.5)^t/800
3 = t/800
t = 2400 years
Thus the object is 2400 years old.
Answer:
81°C.
Explanation:
To solve this problem, we can use the relation:
<em>Q = m.c.ΔT,</em>
where, Q is the amount of heat released from water (Q = - 1200 J).
m is the mass of the water (m = 20.0 g).
c is the specific heat capacity of water (c of water = 4.186 J/g.°C).
ΔT is the difference between the initial and final temperature (ΔT = final T - initial T = final T - 95.0°C).
∵ Q = m.c.ΔT
∴ (- 1200 J) = (20.0 g)(4.186 J/g.°C)(final T - 95.0°C ).
(- 1200 J) = 83.72 final T - 7953.
∴ final T = (- 1200 J + 7953)/83.72 = 80.67°C ≅ 81.0°C.
<em>So, the right choice is: 81°C.</em>
Answer:
Heat going into a substance changes it from a solid to a liquid or a liquid to a gas. Removing heat from a substance changes a gas to a liquid or a liquid to a solid.
Liquid → Gas:
VaporizationGas → Liquid:
CondensationSolid → Liquid:
Melting or fusion
Solid → Gas: Sublimation
Explanation:
