The Alkali Metals- (Group 1A)can be found (excluding hydrogen) in the first column of the periodic table. They all have 1 valence electron and tend to form +1 cations when forming Ionic bonds with non metals.
The Alkali Earth Metals: (Group 2A) can be found in the second column/group on the periodic table. These elements form +2 positively charged cations when forming Ionic bonds with non metals. They also all have 2 valence electrons.
The Halogens: are the elements that make up the second to last group on the periodic table. These elements include Chlorine, Fluorine, Bromine, Iodine, and Astatine. These elements have 7 valence electrons. The usually form a -1 charged anion when forming ionic bonds with metals.
The Noble gases: the very last group on the periodic table. All these elements have 8 valance electrons. Due to the octet rule these atoms are already very stable and rarely react with other elements.
I think u turn down the heat not to sure
1) Na3PO4 (aq) + 3 KOH (aq) → 3 NaOH (aq) + K3PO4 (aq)
Displacement Reaction
2)MgF2 (s) + Li2CO3 (s) → MgCO3 (s) + 2 LiF (s)
Displacement Reaction
3) I don't know
4)2 RbNO3 + BeF2 → Be(NO3)2 + 2 RbF
5)2 AgNO3 (aq) + Cu (s) → Cu(NO3)2 (aq) + 2 Ag (s)
First, we need to get moles of HA =molarity * volume
= 0.1 m * 0.075 L = 0.0075 moles
moles of NaOH = molarity * volume
= 0.1 * 0.03 L = 0.003 moles
from the reaction equation:
HA(aq) + NaOH(aq) → NaA(aq) + H2O(l)
that means the final moles' HA = 0.0075 - 0.003 =0.0045 moles
when the total volume is = 0.075 + 0.03 L = 0.105 L
∴ [HA] = moles / volume
= 0.0045 / 0.105 L = 0.043 m
[A^-] = 0.003 / 0.105 L = 0.029 m
then by using H-H equation:
PH = Pka + ㏒[A^-] / [HA]
by substitution, we can get Pka:
5.5 = Pka+ ㏒ (0.029 /0.043)
∴ Pka = 5.67
when Pka = - ㏒Ka
5.67 = -㏒ Ka
∴Ka = 2 x 10^-6