12. How many grams of beryllium are needed to produce 36.0 g of hydrogen? (Assume an excess of water.) Be(s) + 2H, O() → Be(OH)2 (aq) +H,(g)
a
4.00 g
b. 36.0 g
c. 162 g
d 324 g

Molten iron fills a mould, which has a volume of 200 cm cubed. calculate the volume when the iron cools and solidifies.

Acave rescue team lifts an injured spelunker directly upward and out of a sinkhole by means of a motor-driven cable. the lift is performed in three stages, each requiring a vertical distance of 11.0 m: (a) the initially stationary spelunker is accelerated to a speed of 4.80 m/s; (b) he is then lifted at the constant speed of 4.80 m/s; (c) finally he is decelerated to zero speed. how much work is done on the 78.0 kg rescue by the force lifting him during each stage

Ablock of steel has a density of 0.29lbs per cubic inch. if the block has dimensions of 1 inch by 1 inch by 3 inches, what is its weight? a. 0.29lbs b. 0.58lbs c. 0.87lbs d. 1lbs