Answer:
If you multiply the miles per hour (30) by 60 (the amount of minutes in an hour) you should get the number for miles per minute. if you multiply that number by 60, you should get the number for miles per second.
Answer:
group I: alkali metals
group II (beryllium to radium): alkaline earth metals
group II (scandium to zinc , yttrium to cadmium, lanthanoid series to mercury, actinoid series to copernicium): transition metals
group VII (fluorine to astatine): halogens
group VIII: (helium to radon): noble gases
Explanation:
Answer:
Standard enthalpy of formation of Carbon disulfide CS2 = 87.3 KJ/mol
Explanation:
forming CS2 means that it should in the product side
C(graphite) + O2 → CO2 ΔH = -393.5
2S(rhombic) + 2O2 → 2SO2 ΔH = -296.4 x 2
CO2 + 2SO2 → CS2 + 3O2 ΔH = -1073.6 x -1
the second reaction is multiplied by 2 so that the SO2 and O2 can cancel out.
the third reaction is reversed (multiplied by -1) so that CS2 will be on the product side.
after adding the reaction and cancelling out similarities, the final reaction is: C(graphite) + 2S(rhombic) → CS2
Add ΔH to find the enthalpy of formation of CS2
ΔHf = (-393.5) + (-296.4 x 2) + (-1073.6 x -1) = 87.3 KJ/mol
be aware of signs
Answer:
92.6 g.
Explanation:
- The balanced equation is:
CaC₂ + N₂ → CaCN₂ + C.
- It is clear that 1.0 mole of CaC₂ reacts with 1.0 mole of N₂ to produce 1.0 mole of CaCN₂ and 1.0 mole of C.
- We need to calculate the no. of moles of 265.0 g of CaCN₂ produced using the relation:
n = mass / molar mass = (265.0 g) / (80.102 g/mol) = 3.308 mol.
- We should get the no. of moles of N₂ needed to produce 3.308 mol of CaCN₂.
∵ 1.0 mole of N₂ produces → 1.0 mole of CaCN₂.
<em>∴ 3.308 mole of N₂ produces → 3.308 mole of CaCN₂.</em>
- Now, we can get the grams of N₂ consumed to produce 265.0 g of CaCN₂:
∴ The grams of N₂ = n x molar mass = (3.308 mole)(28.0 g/mol) = 92.63 g = 92.6 g.
The arrangement of valence electrons in metals can be best described by the
A sea of electrons.
