Answer:
Standard pressure is always 1.00atm. Example #1: How many moles of oxygen will occupy a volume of 2.50 L at STP? Standard temperature = 273K law.
Explanation:
Covalent network crystals usually have the highest melting points and boiling points.
Answer: [B]: 12.0 .
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Note: The pH scale ranges from 1 to 14 .
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Answer:
1.75 × 10⁻³ M
Explanation:
Given:
Hardness = 175 mg CaCO₃/L
or mass of CaCO₃ in 1 L = 175 × 10⁻³ grams
Now,
Molar mass of CaCO₃ = 40 + 12 + ( 3 × 12 ) = 100 grams/mol
The concentration of CaCO₃ = number of moles / volume
or
= (175 × 10⁻³ / 100) / 1
or
= 1.75 × 10⁻³ M
Now,
CaCO₃ ⇒ Ca²⁺ + CO₃²⁻
1.75 × 10⁻³ M 1.75 × 10⁻³ M 1.75 × 10⁻³ M
thus,
the concentration of Ca²⁺ ions in water = 1.75 × 10⁻³ M
A homogeneous mixture composed of two or more substances
