Answer:
5.52 g
Explanation:
First we <u>convert the given masses of both reactants into moles</u>, using their <em>respective molar masses</em>:
- 6.30 g NH₃ ÷ 17 g/mol = 0.370 mol NH₃
- 1.80 g O₂ ÷ 32 g/mol = 0.056 mol O₂
Now we <u>calculate with how many NH₃ moles would 0.056 O₂ moles react</u>, using the<em> stoichiometric coefficients</em>:
- 0.056 mol O₂ *
= 0.045 mol NH₃
As there more NH₃ moles than required, NH₃ is the excess reactant.
Then we calculate how many NH₃ moles remained without reacting:
- 0.370 mol NH₃ - 0.045 mol NH₃ = 0.325 mol NH₃
Finally we convert NH₃ moles into grams:
- 0.325 mol NH₃ * 17 g/mol = 5.52 g
Cooling and heating system involves the collection and dissipation of heat appropriately. Heat gradient is important for heat transfer between systems because heat travels from the warmer system to the cooler system. The right medium for heat transfer is also important for this exchange – A good conductor of heat is required.
Answer:
See whole explanation to understand
Explanation:
the reason why there is such a large jump from 2nd to 3rd ionization energy for calcium is because to remove the third electron, a larger amount of energy is required, since the shell is closer to the nucleus, and higher attraction exists between them. This is why the second ionization energy is 1125.4 and then the third IE is 4912.4 which is a very big difference. It's all about the elections and energy!!
Answer:
6. 7870 kg/m³ (3 s.f.)
7. 33.4 g (3 s.f.)
8. 12600 kg/m³ (3 s.f.)
Explanation:
6. The SI unit for density is kg/m³. Thus convert the mass to Kg and volume to m³ first.
1 kg= 1000g
1m³= 1 ×10⁶ cm³
Mass of iron bar
= 64.2g
= 64.2 ÷1000 kg
= 0.0642 kg
Volume of iron bar
= 8.16 cm³
= 8.16 ÷ 10⁶
Density of iron bar
= 7870 kg/m³ (3 s.f.)
7.
Mass
= 1.16 ×28.8
= 33.408 g
= 33.4 g (3 s.f.)
8. Volume of brick
= 12 cm³
Mass of brick
= 151 g
= 151 ÷ 1000 kg
= 0.151 kg
Density of brick
= mass ÷ volume
(3 s.f.)
