An element's atomic number is the

A. weight of the atom.

B. sum of the protons and neutrons in an atom.

C. number of protons in an atom's nucleus.

D. mass of the atom

What defines an exothermic reaction? O A. A reaction that needs heat added O B. A reaction that possesses enthalpy O c. A reaction that relies on collisions O D. A reaction that produces heat

A 0.08541 g sample of gas occupies 10.0-ml at 288.5 k and 1.10 atm. upon further analysis, the compound is found to be 13.068% c and 86.932% br. what is the molecular formula of the compound? (order: c, x)

What subscripts are needed to complete the formula unit Li_N_? 1,1 3,1 1,3 3,3

One liter of a buffer composed of 1.2 m hno2 and 0.8 m nano2 is mixed with 400 ml of 0.5 m naoh. what is the new ph? assume the pka of hno2 is 3.4.

How could Cl change to gain stability?

Select the statements that best describe the properties of an intramolecular sn2 reaction mechanism.

Is a iron nail solid attracted to a magnet and soluble in water

Convert 45.8g of CO2 to mol

Suppose that 0.95 g of water condenses on a 75.0 g block of iron that is initially at 22 °c. if the heat released during condensation is used only to warm the iron block, what is the final temperature (in °c) of the iron block?

How many grams of NaOH are produced with the reaction of 5.00 moles of water?