Answer:
i) Protons and neutrons
ii) Mass number = 15
iii) Atomic number= 12
Explanation: i) The atom is composed of two parts: named as nucleus which contains neutrons and protons which contributes to most of the mass and there is extra nuclear part which consists of electrons which revolve around the nucleus. Thus subatomic particles are found in the nucleus of the atom are protons with positive charge and neutrons with no charge.
ii) Atomic number is equal to the number of protons or the number of electrons for a neutral atom and is specific to a particular element.
Mass number is the sum of number of protons and the number of neutrons.
Given : atomic number of oxygen = 8 = number of protons
Number of neutrons = 7
Thus mass number = number of protons + number of neutrons = 8+7= 15.
iii) Mass number = 25
Number of neutrons = 13
Mass number = number of protons + number of neutrons
25 = number of protons + 13
number of protons= 25-13 = 12
Thus atomic number = number of protons = 12
False.
The correct homonym to fit the following sentence should be "led".
She LED her friends through the woods.
A homonym is a word that is said or spelled the same way as another word but has a different meaning.
In the above sentence: lead and led are homonyms. Lead is a heavy metal while led means guided.
Other examples homonyms are:
*lays - to recline
laze - to recline with extreme prejudice
leis - several flower necklaces
*made - accomplished
maid - young woman
*manner - method
manor - lord's house
Answer:
Aircraft cabins are therefore pressurized to maintained a similar pressure as that experienced at sea level to ensure normal breathing of passengers.
Explanation:
-Air becomes increasingly thinner with increasing altitudes.
-As such, oxygen becomes limited at higher altitudes and makes it difficult or almost impossible to breath a condition called hypoxia.
-Aircraft cabins are therefore pressurized to maintained a similar pressure as that experienced at sea level to ensure normal breathing of passengers.
That looks like helium
since it has 2 protrons, neutrons, and electrons.
Antimony also forms trihalides and pentahalides, such as SbF3 , where its oxidation state is +3, and SbF5 , where its oxidation state is +5