Answer:
6g/mL
Explanation:
The density, which is the mass per unit volume of an object, can be calculated using the formula;
D= m/v
Where; D = density (g/mL)
M = mass of substance (g)
V = volume (mL)
In this question, the object's mass = 15g, volume of water= 2.5 mL, d =?
Therefore,
Density = 15/2.5
Density = 6 g/mL
The object's density is 6g/mL
Answer:
[H₃O⁺] = 2.5 × 10⁻¹⁰ M
pH = 9.6
Explanation:
Step 1: Given data
Concentration of OH⁻ in the solution ([OH⁻]): 4.0 × 10⁻⁵ M
Step 2: Calculate the concentration of H₃O⁺ in the solution
Let's consider the self-ionization of water.
2 H₂O(l) ⇄ H₃O⁺(aq) + OH⁻(aq)
The <em>ion-product of water (Kw)</em> is:
<em>Kw = 1.0 × 10⁻¹⁴ = [H₃O⁺] × [OH⁻]</em>
[H₃O⁺] = 1.0 × 10⁻¹⁴/[OH⁻]
[H₃O⁺] = 1.0 × 10⁻¹⁴/4.0 × 10⁻⁵
[H₃O⁺] = 2.5 × 10⁻¹⁰ M
Step 3: Calculate the pH of the solution
We will use the following expression.
<em>pH = -log [H₃O⁺]</em>
pH = -log 2.5 × 10⁻¹⁰
pH = 9.6
Chemical change, because the atoms are being rearranged and we get a new substance.
Answer:
Mass = 51 g
Explanation:
Given data:
Mass of ammonia formed = ?
Number of moles of hydrogen = 4.50 mol
Solution:
Chemical equation:
N₂ + 3H₂ → 2NH₃
Now we will compare the moles of hydrogen and ammonia.
H₂ : NH₃
3 : 2
4.50 : 2/3×4.50 = 3 mol
Mass of ammonia formed:
Mass = number of moles × molar mass
Mass = 3 mol × 17 g/mol
Mass = 51 g