Answer: 0.887 g of 
should be added to excess HCl(aq).
Explanation:
According to ideal gas equation:
P = pressure of gas = 805 torr = 1.06 atm (760torr=1atm)
V = Volume of gas = 235 ml = 0.235 L
n = number of moles = ?
R = gas constant =
T =temperature =
According to stoichiometry:
1 mole of chlorine is produced by = 1 mole of
Thus 0.0102 moles of chlorine is produced by = 
moles of
Mass of =
0.887 g of should be added to excess HCl(aq).
Answer:
Choices 2 and 4
Explanation:
HCL is formed witthe the elements Hydrogen and Chlorine. Whatever is on the left side of the equation must match up with the right side of the equation.
2. H + Cl --> HCl (we have one hydrogen and one chlorine)
4. 2HCl --> H2 + Cl2 (since the two is distributed to both the H and the Cl, H has 2 and Cl has two on the left side AND on the right side of the equation)
Answer:
197mL of 0,506M HCl
Explanation:
The reaction of HCl + BaCO₃ is:
BaCO₃(s) + 2HCl → BaCl₂(aq) + CO₂ + H₂O.
The moles of BaCO₃ in 9,85 g are:
9,85 g of BaCO₃ × 
= <em>0,0499 moles of BaCO₃</em>
As 1 mol of BaCO₃ reacts with two moles of HCl, for a complete reaction of BaCO₃ to dissolve this compound in water you need:
0,0499 moles of BaCO₃ × 
=<em> 0,0998 moles of HCl</em>
If you have a 0,506M HCl, you need to add:
0,0998 moles of HCl× 
= 0,197 L ≡ 197mL
I hope it helps!
Answer:
(C) Energy is released when the electron is ejected from the atom.
Explanation:
In the Bohr model of the atom, electrons are arranged in energy levels. The electrons in the lowest energy levels are nearest to the nucleus. An electron may move from a lower to a higher energy level by absorbing energy that is equal to the difference between the energies of the higher and lower energy level.
The potential energy of all electrons inside the atom have negative values and an electron which is infinitely far from the nucleus has an electrostatic potential energy of zero.
Energy is absorbed when an electron is removed from the atom (ionization). Hence the process is highly endothermic. Therefore it is false to say that "Energy is released when the electron is ejected from the atom."
I would go with option #4, reduced use of resources!
:V
