1.
V = 200 mL (volume)
c = 3 M = 3 mol/L (concentration)
First we convert mL to L:
200 mL = 0.2 L
Then we calculate the moles using the formula: n = V × c = 0.2 L × 3 mol = 0.6 mol
Finally, we just use the molar mass of CaF2 to calculate the actual mass:
molar mass = 78 g/mol
The formula is: m = n × mm (mass = moles × molar mass)
m = 0.6 mol × 78 g/mol = 46.8 g
2.
For this question the steps are exactly like the first question.
V = 50mL = 0.05 L
c = 12 M = 12 mol/L
n = V × c = 0.05 L × 12 mol/L = 0.6 mol
molar mass (HCl) = 36.5 g/mol
m = n × mm = 0.6 mol × 36.5 g/mol = 21.9 g.
3.
The steps for this question are the opposite way.
m(K2CO3) = 250 g
molar mass = 138 g/mol
n = m ÷ mm = 1.81 mol
c = 2 mol/L
V = n ÷ c = 1.81 mol ÷ 2 mol/L = 0.905 L = 905 mL
<span>There are 3 prime, 2 prime, and 1 prime carbocations that form in the reaction. SN1 reactions favor them in the order of 3, 2, then 1.</span>
Atomic number
26
Atomic mass
55.85 g.mol<span> -1</span>
Electronegativity according to Pauling
1.8
Density
7.8 g.cm-3 at 20°C
Melting point
1536 °C
Boiling point
2861 °C
<span>Vanderwaalsradius </span>
0.126 nm
Ionic radius
0.076 nm (+2) ; 0.064 nm (+3)
Isotopes
8
<span>Electronic shell </span>
[ Ar ] 3d6 4s2
Energy of first ionisation
761 kJ.mol<span> -1</span>
Energy of second ionisation
1556.5 kJ.mol<span> -1</span>
Energy of third ionisation
2951 kJ.mol<span> -1</span>
Standard potential
- o.44 V (Fe2+/ Fe ) ; 0.77 V ( Fe3+/ Fe2+ )
Discovered by
The ancients
<span>
Read more: <span>http://www.lenntech.com/periodic/elements/fe.htm#ixzz4a5WaFZtx</span></span>
Answer:
Like charges repel each other; unlike charges attract. Thus, two negative charges repel one another, while a positive charge attracts a negative charge.
