Answer:
I think the answer should be B. Number of valence electrons
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.
Answer:
53.85%
Explanation:
Data obtained from the question include:
Mass of antimony (Sb) = 27.6g
Mass of Fluorine (F) = 32.2g
Mass of compound = 59.8g
Percentage composition of fluorine (F) =..?
The percentage composition of fluorine can be obtained as follow:
Percentage composition of fluorine = mass of fluorine/mass of compound x 100
Percentage composition of fluorine = 32.2/59.8 x 100
= 53.85%
Therefore, the percentage composition of fluorine in the compound is 53.85%
Protons and neutrons are in the center of the atom, making up the nucleus. The charge on the proton and electron are exactly the same size but opposite. Neutrons have no charge.
A base and an Acid always react to form a salt and water
So, HCl + NaOH —> NaCl + HOH
