Answer:
Explanation:
Group one:
The elements of group one shows +1 charge because these all are metals and lose their one valance electron.
Hydrogen lithium sodium potassium rubidium cesium francium
Group 2:
The elements of group two shows +2 charge because these all alkali metals and lose their two valance electrons.
beryllium magnesium calcium strontium barium radium
Group 3:
The elements of group three-B shoes +3 charge by losing three valance electrons.
Scandium yttrium lanthanum actinium
Group 4:
The elements of group 4th A and 4th B lose four electrons or gain four electrons to complete the octet and shows +4 or -4 charge.
Group 5:
Group 5th elements gain three electrons and shows -3 charge to complete the 8 electrons. (octet).
It involve the elements of group 5th A.
Group 6:
The elements of group 6A gain two electrons to complete the octet and shows -2 charge.
Group 7:
The elements of group 7A gain one electron to complete the octet and shows -1 charge.
Group 8:
The elements of group 8A are noble gases and have complete octet. That's why shows 0 charge.
Answer: The number to the left of AC should be 6.
Explanation: The balanced chemical reaction is one in which the number of atoms of each element on the reactant side must be equal to the number of atoms on product side.
The given equation 
is unbalanced as the atoms on the reactant side are not same as number of atoms on product side. This equation is called as skeletal equation.
The balanced chemical equation is :
Thus the number to the left of AC is 6.
Answer:
the plant population over time has decreased. this could make all other organisms above the plant population numbers decrease as well.
Explanation:
117.22 g are needed to react with an excess of Fe2O3 to produce 156.2 g of Fe.
Explanation:
Moles of Fe = Mass of Fe in grams / Atomic weight of Fe
= 156.2 / 55.847
Moles of Fe = 2.79.
The ratio between CO and Fe id 3 : 2.
Moles CO needed = 2.79 * (3 / 2)
= 4.185.
To calculate Atomic weight of CO,
Atomic weight of carbon = 12.011
Atomic weight of oxygen= 15.9994
Atomic weight of CO = 12.011 + 15.9994 = 28.01 g / mol.
Mass of CO = 4.185 * 28.01 = 117.22 g.
