Answer: Mercury-194 is an unstable isotope and hence is radioactive.
Explanation: Mercury-194 is an isotope of mercury, having formula 
Number of protons in this isotope = 80
Number of neutrons in this isotope = 114
This isotope is radioactive in nature and under decay process by Electron Capture.
Electron capture reactions are the reactions in which a proton in a nucleus absorbs an electron and convert it into neutron. The resulting nucleus will have a decreased atomic number and same atomic mass.
Reaction for electron capture of mercury-194 follows:

Answer:
The nichrome wire is dirty.
The solution is contaminated.
Explanation:
If the nichrome wire is dirty, it may contain sodium contaminants which may be responsible for the yellow flame. The nichrome wire is first inserted into the flame without the sample to check for impurities.
The test solution may also have been contaminated. This leads to the appearance of a colour different from the expected colour of the test cation in the solution.
Answer:
Tetraoxosulphate vi acid (H2SO4)
Explanation:
Becauses it ionizes completely
The balanced reaction is as below
3A₂B + 2DC₃→ 6 AC + D₂B₃
The number that must be to the left of AC is 6
Explanation
- According to the law of mass conservation , the number of atoms in reactant side must be equal to number to the number of atoms in product side.
- Therefore the equation above is balance since it obey the law of mass conservation.
- For example there is 6 atoms of A in reactant side and 6 in product side.
Answer:
A mole is __a substance is defined as: The mass of substance containing the same number of fundamental units as there are atoms in exactly 12.000 g of 12C. Fundamental units may be atoms, molecules, or formula units, depending on the substance concerned.
Explanation: