Answer:The formulas of ionic compounds are:
a)
b)
c)
d)
Explanation:
Formulas for the an ionic compounds is determine by:
Criss-cross method, the oxidation state of the ions gets exchanged and they form the subscripts of the other ions. This results in the formation of a neutral compound.
(a) Copper bromide :Given that it contains
ion.

(b) Manganese oxide : Given that it contains
ion.

(c)Mercury iodide :Given that it contains 

(d) Magnesium phosphate :Given that it contains 

Answer:
In percentage, the sample of C-4 remains = 0.7015 %
Explanation:
The Half life Carbon 14 = 5730 year
Where, k is rate constant
So,
The rate constant, k = 0.000120968 year⁻¹
Time = 41000 years
Using integrated rate law for first order kinetics as:
Where,
is the concentration at time t
is the initial concentration
So,
<u>In percentage, the sample of C-4 remains = 0.7015 %</u>
Molecular formula is an integral multiple of the empirical formula
Speed (m/s) = distance (metres) ÷ time (seconds)
For Track 1: 0.2 ÷ 2 = 0.1m/s
For Track 2: 0.2 ÷ 2 = 0.1m/s
For Track 3: 0.6 ÷ 6 = 0.1m/s
For Track 4: 0.4 ÷ 6 = 0.07m/s
The train on Track 4 had the slowest speed because it's got the shortest speed and it's covering less distance per second therefore it is slower.