Answer:
The chemist would require to use 43.43 grams.
Explanation:
In order to solve this problem we need to know<u> how much do 0.550 moles of selenium weigh</u>. To do that we use selenium's<em> molar mass </em>and multiply it by the given number of moles:
- 0.550 mol * 78.96 g/mol = 43.43 g
The chemist would require to use 43.43 grams.
Answer:
One of the main uses of the cathode ray tube is in the Cathode ray oscilloscope
Explanation:
Cathode rays are produced when a gas in an evacuated glass at very low pressure and high pressure breaks up into positive and negative ions. the negative ions move towards the anode(positive electrode) while the positive ions move towards the cathode(negative electrode), and there they knock off electrons (which are known as cathode rays) from the metal plate of the cathode.
Cathode ray tubes are mainly used in oscilloscopes, television picture tubes and in computer screens.
The cathode ray oscilloscope is used in a.c. and d.c. voltage measurements, observation of waveforms, time measurements, etc.
Answer : The pressure in the flask after reaction complete is, 2.4 atm
Explanation :
To calculate the pressure in the flask after reaction is complete we are using ideal gas equation.
where,
P = final pressure in the flask = ?
R = gas constant = 0.0821 L.atm/mol.K
T = temperature = 
V = volume = 4.0 L
= moles of 
= 0.20 mol
= moles of 
= 0.20 mol
Now put all the given values in the above expression, we get:
Thus, the pressure in the flask after reaction complete is, 2.4 atm
Ideal gases are hypothetical gases whose molecules occupy negligible space and have no interactions, and that consequently obeys the gas laws exactly.
Not exactly sure about the amount...
I hope this helps! :)
