Answer:
a
Explanation:
The formation of ion occurs when an atom that is said to be neutral gains or losses electrons.
At the time it gains electrons, it is regarded that a negative ion (anion) is formed.
When it loses electron, it is regarded that a positive ion (cation) is formed.
Atomic number = No of protons and electrons occurring in a neutral atom.
Given that:
Protons = 14
electron = 18
Net Charge = no of proton - no of electron
= 14 - 18
= -4
Mass number = 14 + 15 = 29
So, the chemical symbol = 
For ion with
27 proton, 32 neutrons and 25 electrons
Net charge = 27 - 25
= +2
Mass number = 27 + 32 = 59
Thus, the chemical symbol = 
Answer:
Salt.
Explanation:
Salt=NaCl
Ionic bonds are made when the two elements are from different sides of the periodic table. On the left, we have our metals. On the right, we have our nonmetals. Sodium is a metal and Chlorine is a gas. Water, sugar, and carbon dioxide are covalent bonds because all the elements are from the right side of the periodic table. Hydrogen is a nonmetal too.
When warm air rises, cooler air will move in to replace it, so wind often moves from colder areas to warmer areas. The greater the difference between the high and low pressure or the shorter the distance between the high and low pressure areas, the faster the wind will blow
So the correct answer will be:
When a high and a low pressure air mass are far apart, air moves slowly from high to low pressure
Answer : The molar heat of fusion for substance X is, 775.6 cal/mol
Explanation :
First we have to calculate the moles of substance X.

Given:
Molar mass of substance X = 58.45 g/mole
Mass of substance X = 326.0 g
Now put all the given values in the above expression, we get:

Now we have to calculate the molar heat of fusion for substance X.

where,
Q = heat releases = 4325.8 cal
= molar heat of fusion for substance X = ?
n = moles = 5.577 mol
Now put all the given values in the above expression, we get:

Thus, the molar heat of fusion for substance X is, 775.6 cal/mol