Answer:
D. AX + BY -> AY + BX
Explanation:
Double replacement:
It is the reaction in which two compound exchange their ions and form new compounds.
AB + CD → AC +BD
So from given list of reactions option D is correct while others are incorrect.
Other examples:
The reaction between sodium chloride and silver nitrate is double displacement reaction.
NaCl + AgNO₃ → AgCl + NaNO₃
The anion and cations of both reactants exchange. The anion of sodium chloride (Cl⁻) combine with cation of silver nitrate (Ag⁺) and form AgCl. While Anion of silver nitrate combine with cation of sodium chloride and form sodium nitrate.
Qualitative chemical and enzyme tests helped Avery identify DNA as the transforming principle by conducting <span>a series of tests to find out if the transforming principle was DNA or a protein and the result is that </span>no protein was present but that DNA was present. Hope this answers your question.
PbO2
You have to take the mass of lead in the problem, and divide by the molar mass.
When you do the same with oxygen, you get a number about twice as large as when you divide the mass of lead by the molar mass of lead. This means that the simplest formula would be PbO2
False: to protect iron from corrosion, keep it near moistureband oxygen.
Stability of atoms is determined by neutron:proton ratio. This n/p ratio is 1:1 for elements below atomic number 20. Hope this helps.