A metal block has a mass of 122 grams and measures 2cm x 2cm x 4cm. What is the density of the block?

How many moles are in 250 grams of tungsten (w)? * 4.4x10^23 moles 4.2x10^23 moles 0.7 moles 1.4 moles

The diagram below shows the movement of particles. what does this piece of evidence best support? the collision theory the maxwell-boltzmann distribution the effect of pressure on reaction rates the effect of temperature on reaction rates

When hydrogen peroxide (h2o2) is added to potassium iodide (ki) solution, the hydrogen peroxide decomposes into water (h2o) and oxygen (o2). the chemical equation for the decomposition reaction is: 2h2o2—> 2h2o + o2. what is the role of the potassium iodide in this reaction? a. reactant. b. product. c. precipitate. d. catalyst.