Answer:
74,67 gr/mol
Explanation:
At STP 1 mole of an ideal gas has volume of 22,4 L. Since we know the volume of the gas we can find the number of moles of the gas. (300 mL=0,3 L)
n=0,3L/22,4 L=0,01339 mol
Since we know weight of the gas as 1 g, we can find the molecular weight as;
MW=1 g/0,01339 mol =74,67 gr/mol
When dissolved in water, acids donate hydrogen ions (H+). Hydrogen ions are hydrogen atoms that have lost an electron and now have just a proton, giving them a positive electrical charge. ... If a solution has a high concentration of H+ ions, then it is acidic.
Answer:
Kinetic energy: 
Velocity: 
Explanation:
From the equations of the photo-electric effect,
We know:
Where,
1.
is the Planck's constant which is 
2.
are the frequency of light emitted and threshold frequencies respectively.
3.
is the kinetic energy of the electrons emitted.
By fact, we come to know that the threshold frequency of Zn is 300nm
And also 
Where ,
1. 
is the speed of light 
2.
is the wavelength.
Thus,
Now to find velocity:
<span> It is a little hard to explain step-by-step what to do so I hope you can follow what to do by looking at how I arranged the equations.
2 H2O(g) --------------------------> 2 H2O(l) -88
2 H2 + O2 ----------------------------> 2 H2O(g) -484
C + O2 ----------------------------> CO2 -393.5
CH4 -------------------------------> C + 2 H2 + 74.8
________________________________________...
CH4 + 2 O2 ---------------------> CO2 + 2 H2O -890.6 kJ
Once you cancel out the substances that appear BOTH on the left AND the right of the arrows you are left with your net equation. </span>
