Answer:
Zero
Explanation:
FrBr is an ionic compound
.
Fr is in Group 1. Br is in Group 17.
The charges on the ions are +1 and -1, respectively.
The compound consists of Fr⁺Br⁻ ions.
However, there are equal numbers of + and - charges, so
The overall charge of the compound is zero.
<span>I believe an oxidation reaction is occurring</span>
The question is incomplete. The complete question is
Two solutions are combined in a beaker. One solution contains 500.0 g of potassium phosphate and the other contains 500.0 g of calcium nitrate. A double displacement reaction occurs. What mass of each of the following substances is present when the reaction stops. A) potassium phosphate remaining B) calcium nitrate g remaining C) calcium phosphate formed D) potassium nitrate g formed
Answer:
a)84.91g
b)8.20g
c)316.4g
d)616.73g
Explanation:
The equation of the reaction:
2K3PO4(aq) + 3Ca(NO3)2 (aq)-------> 6KNO3(aq) + Ca3(PO4)2(s)
Molar mass of potassium phosphate= 212.27 g/mol
Amount of potassium phosphate= 500/212.27= 2.4 moles
Molar mass of calcium nitrate= 164.088 g/mol
Amount of calcium nitrate= 500/164.088=3.05moles
a) amount of potassium phosphate reacted according to reaction equation= 2 moles
Amount of potassium phosphate remaining= 2.4-2=0.4 moles
Mass of potassium phosphate remaining= 0.4×212.27=84.91g
b) Amount of calcium nitrate reacted according to reaction equation=3
Amount of calcium nitrate remaining=3.05-3= 0.05
Mass of calcium nitrate remaining= 0.05×164.088= 8.20g
c) since calcium nitrate is the limiting reactant, we use to estimate the mass of products formed.
From the reaction equation,
3 moles of calcium nitrate yields 1 mole of calcium phosphate
3.05 moles of calcium nitrate yields 3.05/3 = 1.02 moles of calcium phosphate
Molar Mass of calcium phosphate= 310.18 g/mol
Mass of calcium phosphate produced= 1.02×310.18= 316.4g
d)
3 moles of calcium nitrate yields 6 moles of potassium nitrate
3.05 moles of calcium nitrate yields 3.05×6/3= 6.1 moles of potassium nitrate
Molar mass of potassium nitrate = 101.1032 g/mol
Mass of potassium nitrate formed= 6.1× 101.1032= 616.73g
Answer:
One: <u>Selenium</u> is Paramagnetic
Explanation:
Those compounds which have unpaired electrons are attracted towards magnet. This property is called as paramagnetism. Lets see why remaining are not paramagnetic.
Electronic configuration of Scandium;
Sc = 21 = 1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹
Sc³⁺ = 1s², 2s², 2p⁶, 3s², 3p⁶
Hence in Sc³⁺ there is no unpaired electron.
Electronic configuration of Bromine;
Br = 35 = 1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p⁵
Br⁻ = 1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p⁶
Hence in Br⁻ there is no unpaired electron.
Electronic configuration of Magnesium;
Mg = 12 = 1s², 2s², 2p⁶, 3s²
Mg²⁺ = 1s², 2s², 2p⁶
Hence in Mg²⁺ there is no unpaired electron.
Electronic configuration of selenium;
Se = 34 = 1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p⁴
Or,
Se = 34 = 1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4px², 4py¹, 4pz¹
Hence in Se there are two unpaired electrons hence it is paramagnetic in nature.
