C. 14
you would subtract the mass number from the protons or the atomic number because in order to find the mass number you would add the protons and neutrons :)
Answer:
1.0 *10^(-4) mol
Explanation:
For gases:
n1/n2 = V1/V2
n1/3.8*10^(-4) mol = 230 mL/ 860 mL
n1 = 3.8*10^(-4)*230/860 = 1.0 *10^(-4) mol
Burning Mg in the air and reacting with O2 forming a white powder of MnO
So the equation is going to be:
Mn + O2 ⇒ MnO (this equation is not conserved)
to make it equilibrium:
1- First we should put 2Mno to equal the O2 on both sides.
So it will be:
Mg + O2⇒ 2MgO
2- Second we should put 2Mn to equal the Mn on both sides.
2Mg + O2⇒ 2MgO (this equation is conserved)
After putting the physical states the final equilibrium equation is going to be:
Δ
2Mg(s) + O2(g)⇒ 2MgO(s)
Explanation:
- When a bond is formed by transfer of electrons from one atom to another then it results in the formation of an ionic bond.
An ionic bond is generally formed by a metal and a non-metal.
For example, lithium is an alkali metal with atomic number 3 and its electronic distribution is 2, 1.
And, chlorine is a non-metal with atomic number 17 and its electronic distribution is 2, 8, 7.
So, in order to complete their octet lithium needs to lose an electron and chlorine needs to gain an electron.
Hence, both of then on chemically combining together results in the formation of an ionic compound that is, lithium chloride (LiCl).
An ionic compound is formed by LiCl because lithium has donated its valence electron to the chlorine atom.
- On the other hand, if a bond is formed by sharing of electrons between the two chemically combining atoms then it is known as a covalent bond.
For example, 
is a covalent compound as electrons are being shared by each oxygen atom.
Answer:
In the final solution, the concentration of sucrose is 0.126 M
Explanation:
Hi there!
The number of moles of solute in the volume taken from the more concentrated solution will be equal to the number of moles of solute in the diluted solution. Then, the concentration of the first solution can be calculated using the following equation:
Ci · Vi = Cf · Vf
Where:
Ci = concentration of the original solution
Vi = volume of the solution taken to prepare the more diluted solution.
Cf = concentration of the more diluted solution.
Vf = volume of the more diluted solution.
For the first dillution:
26.6 ml · 2.50 M = 50.0 ml · Cf
Cf = 26.6 ml · 2.50 M / 50.0 ml
Cf = 1.33 M
For the second dilution:
16.0 ml · 1.33 M = 45.0 ml · Cf
Cf = 16.0 ml · 1.33 M / 45.0 ml
Cf = 0.473 M
For the third dilution:
20.0 ml · 0.473 M = 75.0 ml · Cf
Cf = 20.0 ml · 0.473 M / 75.0 ml
Cf = 0.126 M
In the final solution, the concentration of sucrose is 0.126 M
