Answer:
d. white blood cells
Explanation:
It is the white blood cells that have the least tendency to cross the blood- brain barrier.
Blood- brain barrier is psychological barrier and restricts substances that circulate into the blood from crossing over the central nervous system.
Water, glucose as well as sodium ions can easily cross the barrier. As these are good for body supply energy to the brain.
10 is mixture of elements and compounds
11 is compound
12-15 are mixture of compounds
Answer:
3 atoms
Explanation:
2 hydrogen atoms and 1 oxygen atom
I am pretty sure nitrogen would be the solvent because solvents are generally the larger amount
Answer:
Tests for unsaturation involves addition across the multiple bonds in the unsaturated compound.
Explanation:
In organic chemistry, we define an unsaturated compound as any compound that contains a double or triple bond. These multiple bonds are also known as pi bonds.
There are two major tests for unsaturation which shall both be discussed here.
The first test for unsaturation is by the use of bromine water. The unknown sample is passed through a solution of bromine water which normally appears reddish brown. The bromine water becomes decolorized due to addition of bromine across the multiple bond. This is a standard test for unsaturation.
Secondly, unsaturated compounds decoulourize a solution of potassium permanganate when passed through it. This alone can not be used as a distinctive test for unsaturation.
Propenoic acid will give a positive test to the both reagents showing that it contains multiple bonds, in this particular instance, a double bond.
