Yes, mass never changes. No exceptions.
Mercury is the only metal that is a liquid at room temperature.
your answer is A.
It is used in thermometer.
D = 0.2 g / ml = 0.2 g / cm³
For example, density of steel is 7.85 g / cm³.
Density of pure water is 1.0 g/cm³. An object which has a density < 1.0 g/cm³ will float in water.
Answer: Material that has a density of 0.2 g/ml ( 0.2 g/cm³ ) is good for making couch cushions.
Mole ratio:
MgCl₂ + 2 KOH = Mg(OH)₂ + 2 KCl
2 moles KOH ---------------- 1 mole Mg(OH)₂
4 moles KOH ------------------- moles Mg(OH)₂
moles Mg(OH)₂ = 4 x 1 / 2
= 2 moles of Mg(OH)₂
molar mass Mg(OH)₂ = 58g/mol
mass of Mg(OH)₂ = n x mm
mass of Mg(OH)₂ = 58 x 2
= 116 g of <span> Mg(OH)₂</span>
hope this helps!