Answer:
σ = 4.998 E-4 C/m²
Explanation:
- 1 Coulomb (C) ≡ 6.241509 E18 electrons (e)
∴ # elect = 6.24 E14 elect
charge (Q):
⇒ Q = (6.24 E14 elect)/( 1 C /6.241509 E18 elect) = 9.998 E-5 C
charge density (σ):
∴ surface area (S) = 0.2 m²
⇒ σ = ( 9.998 E-5 C ) / ( 0.2 m²)
⇒ σ = 4.998 E-4 C/m²
Answer: 8.7 grams
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number 
of particles.
To calculate the moles, we use the equation:
As oxygen is in excess, Aluminium is the limiting reagent and limits the formation of products.
According to stoichiometry:
4 moles of aluminium give = 2 moles of 
Thus 0.17 moles of aluminium give=
Mass of 
Thus the mass of is 8.7 grams
Answer:
The rock cycle
Explanation:
The three types of rocks are related and connected through the rock cycle. Rocks are not formed independently of one another, the process of their formation are interconnected.
Igneous rocks are made from cooling and solidification of magma. These magma are derived from the melting of rocks that have been subjected to high temperature and pressure.
When igneous rocks are formed, they can follow two path ways. They either get transformed to sedimentary rocks or metamorphic rocks.
When igneous rocks are subjected to metamorphic conditions, their mineralogy is altered to form metamorphic rocks.
If igneous rocks gets weathered and broken down by agents of denudation, they end up getting transformed into sedimentary rocks.
<h3>
Answer:</h3>
The centripetal acceleration is 26.38 m/s²
<h3>
Explanation:</h3>
We are given;
- Mass of rubber stopper = 13 g
- Length of the string(radius) = 0.93 m
- Time for one revolution = 1.18 seconds
We are required to calculate the centripetal acceleration.
To get the centripetal acceleration is given by the formula;
Centripetal acc = V²/r
Where, V is the velocity and r is the radius.
Since time for 1 revolution is 1.18 seconds,
Then, V = 2πr/t, taking π to be 3.142 ( 1 revolution = 2πr)
Therefore;
Velocity = (2 × 3.142 × 0.93 m) ÷ 1.18 sec
= 4.953 m/s
Thus;
Centripetal acceleration = (4.953 m/s)² ÷ 0.93 m
= 26.38 m/s²
Hence, the centripetal acceleration is 26.38 m/s²
Answer:
0.01836 M
Explanation:
Again the reaction equation is;
Fe(s) + Mn2+(aq) → Fe2+(aq) + Mn(s)
E°cell= 0.77 V
Ecell= 0.78 V
[Mn2+] = 0.040 M
[Fe2+] = the unknown
n=2
From Nernst's equation;
Ecell= E°cell- 0.0592/n log Q
0.78= 0.77 - 0.0592/2 log [Fe2+] /[0.040]
0.78-0.77= - 0.0592/2 log [Fe2+] /[0.040]
0.01/ -0.0296= log [Fe2+] /[0.040]
-0.3378= log [Fe2+] /[0.040]
Antilog(-0.3378) = [Fe2+] /[0.040]
0.459= [Fe2+] /[0.040]
[Fe2+] = 0.459 × 0.040
[Fe2+] = 0.01836 M
