Answer:
I think c biological processes
Answer:
A
Explanation:
Hot air is less dense therefore it rises. Cold air is more closely packed therefore it is more dense. Less dense things rise while more dense things sink.
The number following the name of the element is the number of subatomic particles inside the nucleus of the atom. This means that it is the mass number of the isotope. The average atomic mass of the element is the sum of the products of the percentage abundance and mass number of the naturally occurring isotopes.
Since, the average atomic mass of the hydrogen is nearest to 1 then, the most abundant isotope should be hydrogen-1.
Boiling point elevation is given as:
ΔTb=iKbm
Where,
ΔTb=elevation in the boiling point
that is given by expression:
ΔTb=Tb (solution) - Tb (pure solvent)
Here Tb (pure solvent)=118.1 °C
i for CaCO3= 2
Kb=2.93 °C/m
m=Molality of CaCO₃:
Molality of CaCO₃=Number of moles of CaCO₃/ Mass of solvent (Kg)
=(Given Mass of CaCO3/Molar mass of CaCO₃)/ Mass of solvent (Kg)
=(100.0÷100 g/mol)/0.4
= 2.5 m
So now putting value of m, i and Kb in the boiling point elevation equation we get:
ΔTb=iKbm
=2×2.93×2.5
=14.65 °C
boiling point of a solution can be calculated:
ΔTb=Tb (solution) - Tb (pure solvent)
14.65=Tb (solution)-118.1
Tb (solution)=118.1+14.65
=132.75
Answer:
The type of allergy test is scratch test.
Explanation:
In a scratch test also called a skin pri c k test or puncture test, an allergy provoking substance placed on the skin is gradually scratched into the skin surface with the aid of a needle or lancet so as to detect bodily reactions to allergens. Some of the types allergens whose reactions are generally tested for include pollen, dust mites, molds and foods.
The scratch test takes about 5 to 10 minutes and it could cause slight pain and the may result in itching feeling at the location where the allergen was introduced.
