A + BC ---> AB + C
So here one reactant (A) is accepting a group which is being given by another compound (BC) however the A is not giving any group / element or ion
So this single displacement
Similarly in the given reaction
the anion OH- is only being replaced
The element Ca accepts OH- and H2O loses the same group to form new element H2
So the correct answer is
Single replacement also known as single displacement.
Answer:
To prepare 1.00 L of 2.0 M urea solution, we need to dissolve 120 g of urea in enough water to produce a total of 1.00 L solution
Explanation:
Molarity of a solute in a solution denotes number of moles of solute dissolved in 1 L of solution.
So, moles of urea in 1.00 L of a 2.0 M urea solution = 2 moles
We know, number of moles of a compound is the ratio of mass to molar mass of that compound.
So, mass of 2 moles of urea = 
Therefore to prepare 1.00 L of 2.0 M urea solution, we need to dissolve 120 g of urea in enough water to produce a total of 1.00 L solution
So, option (C) is correct.
The false positive from the response of hydrogen peroxide and the immunizing circle would be created by poor specificity. The recipe for specificity is TN/TN+FP. False-positive outcomes can be ascribed to meddling substances in nature where the strips are put away or utilized, for example, hydrogen peroxide (H2O2) or fade (hypochlorite).
The balanced equation:
Mg+2HCl⇒ MgCl₂+H₂
A - adolescence.
According to google definitions..
Adolescencenounthe period following the onset of puberty during which a young person develops from a child into an adult.
