Why can't we extract sodium from aqueous solution of sodium chloride

Which real-world scenarios below represent physical and chemical changes? -running a car -exploding fireworks -mixing water and powdered drink mix -combining oil and vinegar to make salad dressing -taking aspirin for a headache -diluting bleach with water-digesting dinner-spreading peanut butter on bread

What is the number of moles in 15.0 g ash3?

Apiece of metal with a length of 1.42 cm was measured using four different instruments. which of the following measurements is the most accurate?