Answer: Option (a) is the correct answer.
Explanation:
A lipid that contains a phosphate group in its molecule is known as a phospholipid.
These are the primary molecules present in a plasma membrane. These tend to contain two hydrophobic fatty acid tails and one hydrophilic head.
Hydrophilic means water loving in nature.
As phosphate group is a polar group due to this the hydrophilic region present in a phospholipid is able to interact with water.
In an amino-alcohol modified phosphate, ester groups, and glycerol, the glycerol is hydrophobic in nature. It also contains two fatty acids and a phosphoric acid which are present as ester. The polar head that mainly consists of phosphate group is hydrophilic and thus, it helps in combining to a water molecules.
Hence, we can conclude that in a phospholipid, amino-alcohol modified phosphate, ester groups, and glycerol are the components which constitute the hydrophilic head.
MASS: generally a measure of an object's resistance to changing its state of motion when a force is applied. It is determined by the strength of its mutual gravitational attraction.
Molecular mass or molecular weight is the mass of a molecule.
Gram formula mass (a.k.a. molar mass) is defined as the atomic mass of one mole of an element, molecular compound or ionic compound. The answer must always be written with the unit g/mol (grams per mole).
Answer:
9.1 KJ
Explanation:
First we must find the number of moles of HBr involved;
number of moles of HBr= mass of HBr/ molar mass of HBr
But molar mass of HBr= 80.91 g/mol
Given mass of HBr from the question= 20.1g
Hence;
Number of moles of HBr= 20.1 g/80.91g
Number of moles of HBr= 0.25 moles of HBr
If 2 moles of HBr has a heat of formation of 72.80KJ
Then 0.25 moles of HBr will have a heat of formation of 0.25× 72.80/2= 9.1 KJ
Therefore; 20.1 g of HBr will have a heat of formation of 9.1 KJ
Answer:
c. relative age
Explanation:
Relative age is a method of describing the age of rocks based on their order of appearance in the geologic column.
Events are denoted by their position in the column.
- The premise of most of the assumptions used relative age determination is based on stratigraphic laws.
- Absolute age gives numeric ages to rocks.
Since Luisa is comparing the age of people based on their position in her family, she is using the concept of relative dating.
