What is the SI base unit of temperature? Celsius kelvin coulomb Fahrenheit

The flesh of a cut apple turns brown when left out in the air. Is this a chemical change or a physical change? Why?

Which has should only be produced in a fume hood? a. Cl2 b. CO2 c. H2 d. H2O

How might you separate a mixture of sand and salt?

A swimming pool, 10.0 m by 4.0 m is filled to a depth of 3.0 m with water at a temperature of 20.0 degrees Celsius. How much energy is required to raise the temperature of the water to 30.0 degrees Celsius.

An unknown radioactive substance has a half-life of 3.20 hours. If 16.5 g of the substance is currently present, what mass A0 was present 8.00 hours ago

What type of rock cannot be changed into a metamorphic rock? A) sedimentary B) igneous C) metamorphic D) magma

What is the most massive element?

A liquid would boil at the lowest temperature at a pressure of

The reaction 2HgO (s) ↽⇀ 2Hg (l) + O2 (g), you produce 1 mole of Hg (I). What is your percentage yield? A) 30% B) 20% C) 50% D) 100%

What are the concentrations of Cu2+, NH3, and Cu (NH3) 42 + at equilibrium when 18.8 g of Cu (NO3) 2 is added to 1.0 L of a 0.