Answer:
13.7 moles
Explanation:
Given data:
Number of moles calcium carbonate = ?
Formula units calcium carbonate= 8.23 × 10²⁴
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For 8.23 × 10²⁴ formula units:
one mole = 6.022 × 10²³ formula units
8.23 × 10²⁴ formula units × 1 mole /6.022 × 10²³ formula units
13.7 moles
Answer:
There will be produced 1.71 moles of B which contain 1.03×10²⁴ molecules
Explanation:
The example reaction is:
2A → 3B
2 moles of A produce 3 moles of B
If we have the mass of A, we convert it to moles and then, we make the rule of three: 29.2 g / 25.6g/mol = 1.14 moles
Therefore 2 moles of A produce 3 moles of B
1.14 moles of A will produce (1.14 . 3) / 2 = 1.71 moles of B are produced
Now we can determine, the number of molecules
1 mol has NA molecules (6.02×10²³)
1.71 moles have (1.71 . NA) = 1.03×10²⁴ molecules
Answer:
protons: 36
neutrons:48
electrons:36
Explanation:
the number of protons in an element is = to the atomic # (36)
the number of neutrons is the atomic mass - atomic # (84-36=48)
In a neutral charged element the # of protons = # of electrons
Answer:
the melting point is the factor what what degrees fahrenheit a metal or other solid substance melts. the significance of knowing the melting point can help you determine how long or how hot to burn the tested object while at the same time determining the safety requirements.
Explanation:
Answer:
- <em>The pH of the solution is </em><u><em>7</em></u>
Explanation:
<em>The pH</em> is a measure of the acidity of the solutions. It is defined as the negative logarithm of the molar concentration of hydrogen ions (H⁺).
<em>The hydrogen ion concentration of this solution is 1 × 10⁻⁷ M.</em>
Hence:
- pH = - log (1 × 10⁻⁷) = - (-7) = 7
This pH corresponds to a neutral solution (neither acid nor alkaline).
You should remember this relation bwtween pH and acidity/alkaliinity:
- Low pH (0.0 or close) corresponds to strong acids
- HIgh pH (14.0 or close) corresponds to strong bases
- Acids have pH between 0.0 and 7.0
- Bases have pH between 7.0 and 14.0
