Which of these are physical changes in matter chech all that apply

Boiling water

A pencil being sharpened

Exploding dynamite

Freezing water

Rotting cheese

What happens to an electron during an electron transition? A. The electron gains mass and falls into the nucleus of the atom. B. The electron flows between continuous energy levels when it gains or loses energy. C.

SeH2 molecule - - How many lone-pairs of electrons are on the central Se atom? H3O + ion - - How many lone-pairs of electrons are on the central O atom? SeO2 molecule - - How many lone-pairs of electrons are on the central Se atom?

How did Democritus describe oil atoms

How many moles of precipitate will be formed when 50.0 mL of 0.300 M AgNO3 is reacted with excess CaI2 in the following chemical reaction? 2AgNO3 (aq) + CaI2 (aq) - -> AgI (s) + Ca (NO3) 2 (aq)

15. What is the name of Fl-? A) Fluorous ion B) Fluorine C) Fluoride ion D) Fluorine ion

A hurricane and a typhoon are the same thing true or false?

Identify the element that chlorine forms a covalent bond with

A child pulls a sled up a snow-covered hill. The child does 405 J of work on the sled. If the child walks 15 m up the hill, how large of a force must the child exert?

A piece of glass with a mass of 32.50 g specific heat of 0.840 J/g*°C and an initial temperature of 115 °C was dropped into a calorimeter containing 57 g of water (specific heat 4.184 J/g*°C).

Which of the following is the most likely description of the product or products of a double-displacement reaction? A) one new compound B) two new compounds C) oxygen and energy D) one new compound and an element