Answer:
It take 3.5 *10² min
Explanation:
Step 1: Data given
Mass of the nickel = 29.6 grams
4.7A
Step 2: The balanced equation
Ni2+ (aq- +2e- → Ni(s)
Step 3: Calculate time
W = (ItA)/(n*F)
⇒ W = weight of plated metal in grams = 29.6
⇒ I = current in coulombs per second.
= 4.7
⇒ t = time in seconds.
⇒ A = atomic weight of the metal in grams per mole. = 58.69
⇒ n = valence of dissolved metal in solution in equivalents per mole. = 2
⇒ F = Faraday's constant in coulombs per equivalent. F = 96,485.309 coulombs/equivalent.
29.6 = (4.7 * t * 58.69)/(2*96485309)
t = 20707 seconds
t =345 minutes = 3.5 * 10² min
It take 3.5 *10² min
A) Magnets can attract through solid materials.
Answer:
59.2 grams
Explanation:
We are given that 70.4% of the weight of the total 200 g of the concentration is made up of nitric acid, the remaining information is not required to solve the problem. Since water and nitric acid are the only components of the solution, the total weight of water is given by:

There are 59.2 grams of water in this solution.
Answer:
Heat lost to the surroundings
Heat lost to the thermometer
Explanation:
All changes in heat, or energy, can be explained. Many of the reactions or changes we see in the world involve the conversion of energy. For example as we heat up a substance (eg. water), the amount of energy we put in should give us an exact temperature. However, this is a "perfect world" scenario, and does not occur in real life. Whenever heat is added to a substance like water, we always need to account for the energy that is going to be lost. For example, heat lost to evaporation or even the effect of measuring the temperature with a thermometer (the introduction of anything including a thermometer will affect the temperature).
Answer:
- 0.0249% Sb/cm

Explanation:
Given that:
One surface contains 1 Sb atom per 10⁸ Si atoms and the other surface contains 500 Sb atoms per 10⁸ Si atoms.
The concentration gradient in atomic percent (%) Sb per cm can be calculated as follows:
The difference in concentration = 
The distance
= 0.2-mm = 0.02 cm
Now, the concentration of silicon at one surface containing 1 Sb atom per 10⁸ silicon atoms and at the outer surface that has 500 Sb atom per 10⁸ silicon atoms can be calculated as follows:

= - 0.0249% Sb/cm
b) The concentration
of Sb in atom/cm³ for the surface of 1 Sb atoms can be calculated by using the formula:

Lattice parameter = 5.4307 Å; To cm ; we have
= 

= 
The concentration
of Sb in atom/cm³ for the surface of 500 Sb can be calculated as follows:

= 
= 
Finally, to calculate the concentration gradient


