Answer:
When you try to move the atoms two close, their positive nuclei repel each other. 2. A covalent bond is an electric force of attraction between two atoms that share outer electrons. ... The protons in each nucleus are repelling each other strongly, it takes more energy to move the atoms closer together at this point.
Explanation:
Answer:
Mass = 10.1 g
Explanation:
Given data:
Mass of Fe₂O₃ produced = ?
Mass of iron rust = 12.0 g
Solution:
Chemical equation:
4Fe + 3O₂ → 2Fe₂O₃
Number of moles of iron:
Number of moles = mass/ molar mass
Number of moles = 12.0 g/ 55.85 g/mol
Number of moles = 0.215 mol
Now we will compare the moles of iron and Fe₂O₃ .
Fe : Fe₂O₃
4 : 2
0.215 : 2/4×0.125 = 0.063 mol
Mass of Fe₂O₃ :
Mass = number of moles × molar mass
Mass = 0.063 mol × 159.7 g/mol
Mass = 10.1 g
The ozone layer acts as an invisible shield and protects us from harmful ultraviolet (UV) radiation from the sun. In particular, the ozone layer protects us from the UV radiation, known as UV-B, which causes sunburn.
Ozone is a colorless, odorless reactive gas comprised of three oxygen atoms.
Answer:
meteorologist, barometers, anemometer, thermometer, balloon, satellites, station models, isotherms, isobars
Explanation:
Answer:
Explanation:
This is an example of back titration.
You add a known excess of HCl to the CaCO₃. Some of it reacts with the CaCO₃.
You titrate the left-over HCl.
From the difference you can calculate the amount of CaCO₃.
100.09
CaCO₃ + 2HCl ⟶ CaCl₂ + H₂CO₃
m/g: 1.2450
V/mL: 65.00
c/mol·L⁻¹: 0.4984
NaOH + HCl ⟶ NaCl + H₂O
V/mL: 37.15
c/mol·L⁻¹: 0.2065
1. Total moles of HCl
2. Excess moles of HCl
3. Moles of HCl that reacted
n = (32.40 - 7.671) mmol HCl = 24.72 mmol HCl
4. Moles of CaCO₃
5. Mass of Ca