So boron has an electronic configuration of 1S2 2S2 2P1 and the element with an atomic number of 3 is Lithium which has an electronic configuration of 1S2 2S1.
So the answer is 1S2 2S1.
Answer:
2
Explanation:
2 lone pairs on the central atom of BrF3.
In order to calculate the final volume of the gas, we may apply Charles Law, which states that for a fixed amount of gas subject to a fixed amount of pressure, the volume and temperature of a gas are directly proportional. This is:
V/T = constant
Using this equation,
5/298 = V/278
V = 4.66 L
The final volume of the gas is 4.66 liters
Answer: B. False
Explanation: A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
Example:
Thus as we can see sodium ion 
is being replaced by ammonium ions 
and thus positive ions replace positive ions only and not negative ions.
