Answer:
450. g of 0.173 % KCN solution contains 779 mg of KCN.
Explanation:
Mass of the solution = m
Mass of the KCN in solution = 779 mg
Mass by mass percentage of KCN solution = 0.173%



1 mg = 0.001 g
m = 450,289 mg × 0.001 g = 450.289 mg ≈ 450. g
450. g of 0.173 % KCN solution contains 779 mg of KCN.
Answer:
metal Atom
Explanation:
every transition metal atom are responsible for the flame color. Some metal are also confirmed by flame test.
Answer:
The element will be 
Explanation:
Given that,
Number of proton = 80
Number of neutron = 81
Number of electron = 79
We know that,
The atomic number is equal to the number of proton.
So, the atomic number is 80.
According to atomic number,
The element will be mercury.
We need to calculate the atomic mass
Using formula of atomic mass

Put the value into the formula


We need to find the element
Using atomic mass and atomic number


So, the element will be

Put the value of A and Z
Hence, The element will be 
Answer:
Covering electrical wires in plastic guarantees that the electrons flowing through the wires will not flow through your body when the wire is touched.
Explanation:
"The purpose of insulation covering the metal part of an electrical wire is to prevent accidental contact with other conductors of electricity, which might result in an unintentional electric current through those other conductors."
https://www.allaboutcircuits.com/worksheets/wire-types-and-sizes/#:~:text=Most%20electrical%20wire%20is%20covered,or%20plastic%20coating%20called%20insulation.&text=The%20purpose%20of%20insulation%20covering,current%20through%20those%20other%20conductors.
https://www.hunker.com/13414152/why-are-electrical-wires-covered-in-plastic