Which of the following phase changes is an exothermic change!

sublimation

deposition

vaporization

Melting

Ammonia nh3 chemically reacts with oxygen gas o2 to produce nitric oxide no and water h2o. what mass of water is produced by the reaction of 8.45g of oxygen gas? round your answer to 3 significant digits.

How many grams do 3.6*10^20 atoms of silicon weigh?

Chromatography Portfolio 5. What evidence is there that marker ink is a mixture? 6. Each compound in the marker ink is represented by a color. Did one compound travel farther than others? Explain why you think that this is the case. 7.

Which statement best explains why a salt solution conducts electricity? The salt crystals dissolve and form bridges by which electric charges move. The ions move freely in water but lose their charges.

Find the molarity of a solution that has 25.5 g kbr dissolved in 1.75 l of solution

What kind of reaction occurs when you mix aqueous solutions of barium sulfide and sulfuric acid?

What is true about empathy? Most anyone can learn this skill. Not everyone can learn this skill. It is a desirable attribute. choices A and C

What effect can new observations have on a scientific theory

The total number of valence electrons in the phosphate ion is

The reaction below has an equilibrium constant kp=2.2*106 at 298 k. 2cof2 (g) ⇌co2 (g) + cf4 (g) calculate kp for the reaction below. cof2 (g) ⇌12co2 (g) + 12cf4 (g)