Answer:
10
Explanation:
Sodium has 11 electrons when it is neutral. This sodium isn't neutral, it has a +1 charge. The +1 charge means it has lost 1 electron.
11 - 1 = 10
The Calcium ion is an Alkaline earth metal and wants to give up the 2 s orbital elections and become a +2 cation.
Oxygen has six valence electrons and is looking to gain two electrons to complete the octet (8) electron count in the valence shell making it a -2 anion.
When the charges of the Calcium +2 and the Oxygen -2 are equal and opposite, the ions for an electrical attraction. (Remember Paula Abdul told us "Opposites Attract")
This one to one ratio of charges makes the formula CaO
The little number you see to the right of the symbol for an element is called a subscript.
Answer:
The mole fraction of N₂ is 0.26.
Explanation:
The pressure exerted by a particular gas in a mixture is known as its partial pressure. So, Dalton's law states that the total pressure of a gas mixture is equal to the sum of the pressures that each gas would exert if it were alone:
PT = PA + PB
This relationship is due to the assumption that there are no attractive forces between the gases.
Dalton's partial pressure law can also be expressed in terms of the mole fraction of the gas in the mixture. The mole fraction is a dimensionless quantity that expresses the ratio of the number of moles of a component to the number of moles of all the components present.
So in a mixture of two or more gases, the partial pressure of gas A can be expressed as:
PA = XA * PT
In this case:
- PA= PN₂= 300 torr
- XA=XN₂= ?
- PT= 1.50 atm= 1140 torr (being 1 atm= 760 torr)
Replacing:
300 torr= XN₂*1140 torr
Solving:

XN₂= 0.26
<u><em>The mole fraction of N₂ is 0.26.</em></u>
Answer:
397782000 m²
Explanation:
Given data:
123000 m × 3234 m =?
Solution:
123000 m × 3234 m = 397782000 m²
when we multiply the given quantities having same unit i.e meter the answer should be m² . It could be the area, and its unit is m².
Area = length (m) × width (m)