You should get 5.05 x 10^23 moles.
Answer:
The correct answer is <u>Option</u><u>-</u><u>B</u> (Convert grams of Mg to moles)
Explanation:
In stoichiometry problems the first step is always to balance the given unbalanced chemical equation. In our case the given equation is already balanced hence, we looked for the second step.
As Niven wants to calculate the mass of MgO (which is the product) with respect to Mg (reactant) hence here comes another important rule. In such cases if one wants to compare masses of two reactants or reactant product. or product product then one should first convert the given mass into moles, also the same conversion for the second mass and then compare the moles and at last convert the moles back into mass. So, the flow chart should be like,
Mass (Mg) → Moles (Mg) : (MgO) Moles ← (MgO) Mass
After finding moles following step take place,
Moles (MgO) → Mass (MgO)
Answer:
0.200 M
Explanation:
Step 1: Given data
- Mass of CoCl₂ (m): 2.60 g
- Molar mass of CoCl₂ (M): 130. g/mol
- Volume of solution (V): 100. mL (0.100 L)
Step 2: Calculate the moles (n) of CoCl₂ (solute)
We will use the following expression.
n = m / M
n = 2.60 g / (130. g/mol) = 0.0200 mol
Step 3: Calculate the molar concentration of the solution
Molarity is equal to the moles of solute divided by the liters of solution.
M = n/V
M = 0.0200 mol/0.100 L = 0.200 M
Ionization energy is the amount of energy required to remove the electron that is most loosely bound of an isolated gaseous atom to form a cation.
Electron affinity is the amount of energy released when an electron is added to a neutral atom or a molecule in a gaseous state to form negation ion.
The difference of ionization energy and electron affinity is ionization energy is the required energy to remove an electron from a neutral atom. Whereas, electron affinity is the energy change when a neutral atom attracts an electron to become a negative ion.
The group of elements which have the lowest ionization energy are the alkali metals