Answer : (C) Hafnium is the most likely identity of the given substance.
Solution : Given,
Mass of given substance (m) = 46.9 g
Volume of given substance (V) = 3.5 
First, find the Density of given substance.
Formula used :

Now,put all the values in this formula, we get
= 13.4 g/
So, we conclude that the density of given substance (13.4 g/
) is approximately equal to the density of Mercury and Hafnium (13.53 and 13.31 g/
respectively).
According to the question the substance is solid at room temperature but Mercury is liquid at room temperature. So, Mercury is not identical to the given substance.
Another element i.e, Hafnium is the element whose density is approximately equal to the given substance and also solid at room temperature. And we know that the melting point of solid is high.
So, Hafnium is the most likely element which is the identity of the given substance.
Answer:
0.85 mole of PBr3.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is given below:
3Br2 + 2P —> 2PBr3
From the balanced equation above,
3 moles of Br2 reacted to produce 2 moles of PBr3.
Therefore, 1.27 moles of Br2 will react to produce = (1.27 x 2)/ 3 = 0.85 mole of PBr3.
Therefore, 0.85 mole of PBr3 is produced by the reaction.
Answer:
0.50 M
Explanation:
Given data
- Mass of sodium sulfate (solute): 7.1 g
- Volume of solution: 100 mL
Step 1: Calculate the moles of the solute
The molar mass of sodium sulfate is 142.04 g/mol. The moles corresponding to 7.1 grams of sodium sulfate are:

Step 2: Convert the volume of solution to liters
We will use the relation 1 L = 1000 mL.

Step 3: Calculate the molarity of the solution

Answer:
C
Explanation
On the reactants side there is 4 Hydrogen atoms in total and two oxygen atoms on the left however on the right there is two hydrogen atoms and one oxygen atom. Leaving this equation unbalanced