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.
The accepted concentration of chlorine is 1.00 ppm that is 1 gram of chlorine per million of water.
The volume of water is 
.
Since, 1 gal= 3785.41 mL
Thus, 
Density of water is 1 g/mL thus, mass of water will be 
.
Since, 1 grams of chlorine →
grams of water.
1 g of water →
g of chlorine and,
of water →86.6 g of chlorine
Since, the solution is 9% chlorine by mass, the volume of solution will be:
Thus, volume of chlorine solution is 9.62\times 10^{2} mL.
Answer:
Heat required = 13,325 calories or 55.75 KJ.
Explanation:
To convert a water to steam at 100 degree celsius to vapor, we have to give latent heat of vaporization to water
Which equals ,
Q = mL,
Where, m is the mass of water present
L = specific latent heat of vaporization
Here , m= 25 gram
L equals to 533 calories (or 2230 Joules)
So, Q = 25×533 = 13,325 Calories
Or , Q = 55,750 Joules = 55.75 KJ
so, Heat required = 13,325 calories or 55.75 KJ.
Molar mass O2 = 31.99 g/mol
Molar mass CO2 = 44.01 g/mol
Moles ratio:
<span>C3H8 + 5 O2 = 3 CO2 + 4 H2O
</span>
5 x 44.01 g O2 ---------------- 3 x 44.01 g CO2
( mass of O2) ------------------ 37.15 g CO2
mass of O2 = 37.15 x 5 x 44.01/ 3 x 44.01
mass of O2 = 8174.8575 / 132.03
mass of O2 = 61.916 g
Therefore:
1 mole O2 ----------------- 31.99 g
moles O2 -------------------- 61.916
moles O2 = 61.916 x 1 / 31.99
moles = 61.916 / 31.99 => 1.935 moles of O2
The two main types of chemical bonds are ionic and covalent bonds. An ionic bond essentially donates an electron to the other atom participating in the bond, while electrons in a covalent bond are shared equally between the atoms. The only pure covalent bonds occur between identical atoms.
