Answer : The correct option is, (b) 22.5 M
Explanation : Given,
Mass of calcium nitrate tetrahydrate = 266 g
Molar mass of calcium nitrate tetrahydrate = 236.15 g/mole
Volume of solution = 
Molarity : It is defined as the moles of solute present in one liter of solution.
Formula used :
Now put all the given values in this formula, we get:
As calcium nitrate tetrahydrate dissociate to give 1 mole of calcium ion, 2 moles of nitrate ion and 4 moles of water.
The concentration of nitrate ion = 
Thus, the concentration of nitrate ion is, 22.5 M
17.8 mL NaOH
<em>Step 1.</em> Write the chemical equation
Fe^(2+) + 2NaOH → Fe(OH)2 + 2Na^(+)
<em>Step 2.</em> Calculate the moles of Fe^(2+)
Moles of Fe^(2+) = 500 mL Fe^(2+) × [0.0230 mmol Fe^(2+)]/[1 mL Fe^(2+)]
= 11.50 mmol Fe^(2+)
<em>Step 3.</em> Calculate the moles of NaOH
Moles of NaOH = 11.50 mmol Fe^(2+) × [2 mmol NaOH]/[1 mmol Fe^(2+)]
= 23.00 mmol NaOH
<em>Step 4.</em> Calculate the volume of NaOH
Volume of NaOH = 23.00 mmol NaOH × (1 mL NaOH/1.29 mmol NaOH)
= 17.8 mL NaOH
Answer: Yes! you're all good. Alkali metals in group 1 are the most metallic :)
Answer:
- <em><u>Option A. </u></em><u><em>2KClO₃ → 2KCl + 3O₂</em></u>
Explanation:
There are five basic general types of chemical reactions:
- Synthesis or combination reaction
- Single replacement reactions
- Double replacement reactions
The given reactions are:
- <u>2KClO₃ → 2KCl + 3O₂</u>
Which is, indeed, a decomposition reaction because the reactant, KClO₃, is a single substance that undergoes a reaction in which it yields two new substances, known as products: KCl and O₂.
- <u>4Na + O₂ → 2Na₂O</u> is a synthesis or combination reaction because two reactants, Na and O₂, combine for the formation of one single new product, Na₂O.
- <u>ZnS + 3 O₂ → 2ZnO + 2SO₂ </u>is a single replacement reaction because oxygen is replacing Zn and S in ZnS to form ZnO and plus SO₂.
- <u>2NaBr + CaF₂ → 2NaF + CaBr₂ </u>is a double replacement reaction because two ions (Br⁻ from NaBr and F⁻ from CaF₂) are exchanging places with other two ions (Na⁺ from NaBr and Ca²⁺ from CaF₂) two form two new ionic compounds (NaF and CaBr₂).
