Answer:
The time required for the coating is 105 s
Explanation:
Zinc undergoes reduction reaction and absorbs two (2) electron ions.
The expression for the mass change at electrode
is given as :

where;
M = molar mass
Z = ions charge at electrodes
F = Faraday's constant
I = current
A = area
t = time
also;
=
; replacing that into above equation; we have:
---- equation (1)
where;
A = area
d = thickness
= density
From the above equation (1); The time required for coating can be calculated as;
![[ \frac{20 cm^2 *0.0025 cm*7.13g/cm^3}{65.38g/mol}*2 \frac{moles\ of \ electrons}{mole \ of \ Zn} * 9.65*10^4 \frac{C}{mole \ of \ electrons } ] = (20 A) t](https://tex.z-dn.net/?f=%5B%20%5Cfrac%7B20%20cm%5E2%20%2A0.0025%20cm%2A7.13g%2Fcm%5E3%7D%7B65.38g%2Fmol%7D%2A2%20%5Cfrac%7Bmoles%5C%20of%20%5C%20electrons%7D%7Bmole%20%5C%20of%20%5C%20Zn%7D%20%2A%209.65%2A10%5E4%20%5Cfrac%7BC%7D%7Bmole%20%5C%20of%20%5C%20electrons%20%7D%20%20%5D%20%3D%20%2820%20A%29%20t)

= 105 s
Explanation:
The atoms are chemically bonded together, and they retain their individual physical and chemical properties.
<h2>5060 have three significant figures : Explanation given below </h2>
Explanation:
Significant figures
The significant figures (also known as the significant digits and decimal places) of a number are digits that possess certain meaning .
It includes all digits except: zeros
Rules to find significant figures
1.All non-zero digits are considered significant. For example, 23 has two significant figures.
2.Zeros in between two non-zero digits are significant: like in 202.1201 has seven significant figures.
3.Zeros to the left of the significant figures are not significant. For example, .000021 has two significant figures, zeros have no value .
4.Zeros to the right of the significant figures are significant.
That is the reason in number 5060 , it has 3 significant figures .
Hydrogen bonds are not like covalent bonds. They are nowhere near as strong and you can't think of them in terms of a definite number like a valence. Polar molecules interact with each other and hydrogen bonds are an example of this where the interaction is especially strong. In your example you could represent it like this:
<span>H2C=O---------H-OH </span>
<span>But you should remember that the H2O molecule will be exchanging constantly with others in the solvation shell of the formaldehyde molecule and these in turn will be exchanging with other H2O molecules in the bulk solution. </span>
<span>Formaldehyde in aqueous solution is in equilibrium with its hydrate. </span>
<span>H2C=O + H2O <-----------------> H2C(OH)2</span>
Answer:
34.2 g is the mass of carbon dioxide gas one have in the container.
Explanation:
Moles of
:-
Mass = 49.8 g
Molar mass of oxygen gas = 32 g/mol
The formula for the calculation of moles is shown below:
Thus,

Since pressure and volume are constant, we can use the Avogadro's law as:-
Given ,
V₂ is twice the volume of V₁
V₂ = 2V₁
n₁ = ?
n₂ = 1.55625 mol
Using above equation as:
n₁ = 0.778125 moles
Moles of carbon dioxide = 0.778125 moles
Molar mass of
= 44.0 g/mol
Mass of
= Moles × Molar mass = 0.778125 × 44.0 g = 34.2 g
<u>34.2 g is the mass of carbon dioxide gas one have in the container.</u>