A block of lead has dimensions of 4.50cm by 5.20cm by 6.00 cm. The block weighs 1587 g. From this information, calculate the density of lead.

An atom is made of 5 protons, 6 neutrons, and 7 electrons. Another atom is made of 6 protons, 5 neutrons, and 3 electrons. What can you say about these two atoms?

How is enthalpy used to predict whether a reaction is endothermic or exothermic? when the enthalpy of the reactants is higher than the enthalpy of the products, the reaction is endothermic.

A 1.000 mL sample of acetone, a common solvent sometimes used as a paint remover, was placed in a small bottle whose mass was known to be 38.0015 g. The following values were obtained when the acetone-filled bottle was weighed: 38.7798 g, 38.

At 40°c, the ion-product constant of water, kw, is 2.88*10-14. what is the ph of pure water at 40°c?

How do you tell if a reaction is endothermic or exothermic using only the written formula

In what layer of the skin is melanin found? What does melanin do for skin cells?

An exothermic reaction?

How many atoms of Fluorine are in 595.85g of SeO2F2? A: 6.02 x 10^23 B: 1.204 x 10^24 C: 2.408 x 10^24 D: 4.816 x 10^24

Describe how NH3 and CF4 satisfies the octet for all atoms.

What two items must be equal for a nuclear equation to be balanced?