First find the RFM (Relative Formula Mass) using a periodic table
the RFM of Ca(OH)2 is = 74
then use the equation Moles = Mass / RFM
Moles = 7.4 / 74 = 0.1mol
<span>hope that helps</span>
Answer:
8.33 hours
Explanation:
In order to solve this problem, we must apply Graham's law of diffusion in gases. Graham's law states that the rate of diffusion of a gas is inversely proportional to the square root of its vapour density. For two gases we can write;
R1/R2=√d2/d1
Where;
R1= rate of diffusion of hydrogen
R2= rate diffusion of unknown gas
d1= vapour density of hydrogen
d2= vapour density of the unknown gas
Volume of hydrogen gas = 360cm^3
Time taken for hydrogen gas to diffuse= 1 hour =3600 secs
R1 = 360 cm^3/3600 secs = 0.1 cm^3 s-1
Vapour density of unknown gas = 25
Vapour density of hydrogen = 1
Substituting values,
0.1/R2 = √25/1
0.1/R2 = 5/1
5R2 = 0.1 × 1
R2 = 0.1/5
R2= 0.02 cm^3s-1
Volume of unknown gas = 600cm^3
Time taken for unknown gas to diffuse= volume of unknown gas/ rate of diffusion of unknown gas
Time taken for unknown gas to diffuse= 600/0.02
Time= 30,000 seconds or 8.33 hours
<span>H</span>₃<span>PO</span>₄<span> - Phosphoric Acid :
H</span>₃<span>PO</span>₄<span> = 1.0 * 3 + 31.0 + 16.0 * 4 = 98.0 g/mol
hope this helps!</span>
Answer:
rest will do later mom is calling me plz understand promise will do it
Explanation:
- Elements and compounds are similar in that they are both made of atoms and in some cases molecules.
- Methods of Breaking Down Compounds
- The only way to break down a compound is through a chemical change. Sometimes, energy is needed for a chemical change to happen. Two ways to add energy to break down a compound are to apply heat and to apply an electric current.
Answer:
A.
Explanation:
They lose 1 electrons in their outermost shell.
The proton to electron ratio become unbalanced where the proton overpowers.
Therefore, leaving the ion positively charged.
