Why does lowered air pressure allow water to boil at room tempurature? apex

Ablock of aluminum is dropped into a graduated cylinder with an initial volume of water at 75ml and the volumes rises to 90ml. if the block has a mass of 40.5 g what is its density ?

Question 17 hydrogen is manufactured on an industrial scale by this sequence of reactions: +ch4gh2og ⇌ +cog3h2g k1 +cogh2og ⇌ +co2gh2g k2 the net reaction is: +ch4g2h2og ⇌ +co2g4h2g k write an equation that gives the overall equilibrium constant k in terms of the equilibrium constants k1 and k2. if you need to include any physical constants, be sure you use their standard symbols, which you'll find in the aleks calculator.

Aparticular radioactive nuclide has a half-life of 1000 years. what percentage of an initial population of this nuclide has decayed after 3500 years?