Answer:
MgO- magnesium oxide
Cu(NO3)2- copper(11)nitrate
Li2CO3- lithium carbonate
Answer:
4.52 mol/kg
Explanation:
Given data:
Mass of lithium fluoride = 22.1 g
Mass of water = 188 g
Molality = ?
Solution:
Molality:
It is the number of moles of solute into kilogram of solvent.
Formula:
Molality = number of moles of solute / kilogram solvent
Mathematical expression:
m = n/kg
Now we will convert the grams of LiF into moles.
Number of moles = mass/ molar mass
Number of moles = 22.1 g/ 26 g/mol
Number of moles = 0.85 mol
Now we will convert the g of water into kg.
Mass of water = 188 g× 1kg/1000 g = 0.188 kg
Now we will put the values in formula.
m = 0.85 mol / 0.188 kg
m = 4.52 mol/kg
Cadium
Down a period, atomic radii decrease from left to right due to the increase in the number of protons and electrons across a period.
Answer:
1s2 2s2 2p6 3s2 3p6
Explanation:
Calcium is the 20th element. It has 20 electrons in it's neutral state. The electronic configuration is given as;
1s2 2s2 2p6 3s2 3p6 4s2
However in the compound; calcium chloride, it does not exist in it's neutral state.
CaCl2 --> Ca2+ + Cl-
In Ca2+ state, it has lost two electrons, The total number of electrons becomes; 20 - 2 = 18 electrons.
The electronic configuration is given as;
1s2 2s2 2p6 3s2 3p6
Answer:
Order zero
Explanation:
Let's consider the decomposition of ammonia to nitrogen and hydrogen on a tungsten filament at 800°C.
2 NH₃(g) → N₂(g) + 3 H₂(g)
The generic rate law is:
rate = k × [NH₃]ⁿ
where,
rate: reaction rate
k: rate constant
n: reaction order
When n = 0, we get:
rate = k × [NH₃]⁰ = k
As we can see, when the reaction order with respect to ammonia is zero, the reaction rate is independent of the concentration of ammonia.
