What is the number placed in front of a compound to balance a chemical reaction?

Find the velocity of a swimmer who swims exactly 220 m toward the shore in 72 s. a 3.1 m/s b 0.33 s/m c 3.06 s d 0.33 m/s

How many helium atoms are in 12.00 grams of helium?

Explain why many compounds that contain one or more hydrogen atoms are not classified as arrhenius acids

45 2.0 2. How many joules of heat are needed to raise the temperature of 048 kg of aluminum from 21°C to 94°C, if the specific heat of aluminum is 900 J/g °C?

1 2 3 4 5 6 7 8 9 10 Sheri studies to get good grades because this is what her parents expect of her. She wants to make them proud. This is an a. Intrinsic motivational statement c. Both of these b. Extrinsic motivational statement d. None of these

Reactions that affect the nucleus of an atom are called? A. Fusions B. Radioactive decays C. Nuclear reactions D. Fissions

The amplitude of a wave is most directly related to what wave characteristic? Crest length Frequency Wavelength Wave height

Why is oil unable to dissolve well in water? Water is polar and oil is nonpolar, which means they have no attraction for each other. Oil molecules are too large to fit between the closely spaced water molecules in the liquid state.

The fertilizer ammonium sulfate is prepared by the reaction between ammonia and sulfuric acid. How many kg of ammonia are needed to produce 1x10^5 kg of (NH4) 2SO4?

The conversion of chemical energy to mechanical energy is best described by which example? A. sunlight warming the ground B. electricity boiling water C. fuel being combusted to power a rocket