How many grams of dofium can react in 250. mL of 3.00 M HCl
The correct answer and explanation is:
To determine how many grams of dofium can react with 250. mL of 3.00 M HCl, we must know the balanced chemical equation for the reaction between dofium and HCl.
Let’s assume that dofium (Df) reacts with hydrochloric acid (HCl) in a 1:2 mole ratio — similar to how some metals (like magnesium) react with hydrochloric acid: Df (s)+2HCl (aq)→DfCl2(aq)+H2(g)\text{Df (s)} + 2 \text{HCl (aq)} \rightarrow \text{DfCl}_2 \text{(aq)} + \text{H}_2 \text{(g)}
Step 1: Calculate moles of HCl
Given:
- Volume of HCl = 250. mL = 0.250 L
- Molarity of HCl = 3.00 mol/L
Moles of HCl=M×V=3.00 mol/L×0.250 L=0.750 mol\text{Moles of HCl} = M \times V = 3.00 \, \text{mol/L} \times 0.250 \, \text{L} = 0.750 \, \text{mol}
Step 2: Use mole ratio to find moles of Df
From the balanced equation, 1 mole of Df reacts with 2 moles of HCl. Moles of Df=0.7502=0.375 mol\text{Moles of Df} = \frac{0.750}{2} = 0.375 \, \text{mol}
Step 3: Convert moles of Df to grams
To find grams, we need the molar mass of dofium. If dofium is a fictional element, we can assign it a hypothetical molar mass. Let’s assume dofium has a molar mass of 200. g/mol (for calculation purposes). Mass=moles×molar mass=0.375×200=75.0 g\text{Mass} = \text{moles} \times \text{molar mass} = 0.375 \times 200 = 75.0 \, \text{g}
✅ Final Answer:
75.0 grams of dofium can react with 250. mL of 3.00 M HCl.
📘 Explanation (300 words):
To determine how much of a substance (in grams) can react with an acid like HCl, we start by calculating the number of moles of HCl present using the formula: Moles=Molarity×Volume\text{Moles} = \text{Molarity} \times \text{Volume}
Molarity tells us how many moles of solute (in this case, HCl) are present per liter of solution. Since 250. mL is 0.250 L, we multiply 3.00 mol/L by 0.250 L to get 0.750 moles of HCl.
Next, we need to understand how the dofium reacts. If it reacts like a typical Group 2 metal (e.g., Mg), one mole of dofium would react with two moles of HCl, forming a salt (dofium chloride) and hydrogen gas. Using the mole ratio from the balanced equation, we find that 0.750 moles of HCl would react with 0.375 moles of dofium.
Now, to convert moles to grams, we multiply by the molar mass. Since dofium is fictional, we estimate a reasonable molar mass—200 g/mol. Multiplying 0.375 moles by 200 g/mol gives 75.0 grams.
This step-by-step process—calculating moles from molarity and volume, applying mole ratios from the chemical equation, and converting moles to grams—is fundamental in stoichiometry, helping chemists predict the quantities of substances involved in reactions.