for the following equilibrium: 2a b⇌2c if initial concentrations are [a]=0.80 m,[b]=0.95 m,[c]=2.5 m, and at equilibrium [c]=1.9 m, what is the equilibrium constant?

It conforms what ever surface its in.

The density of water is 1 g/cm cubed and in order for the pebble to sink its density has to be greater than the density of water and in order for the twig to float its density has to be less than the density of water

B.1 - hydrogren-1 can only mean there is 1 neutron. it's obvious there is 1 proton or else it wouldn't be hydrogen, so they wouldn't put a number after it unless they were indicating the number of neutrons