when sodium metal is dropped in water, hydrogen gas in liberated due to extreme heat released as the reaction is exothermic, gas catches fire.
Density = Mass / Volume
V = 1.00 * 4.00 * 2.50 = 10 cm³
22.57 g/cm³ = Mass / 10 cm³
M = 22.57 g/cm³ * 10 cm³
M = 225.7 g
Answer: The mass of the block of osmium is 225.7 g.
0.004382166 Make sure to round to the right amount of Sig Figs
Answer: Yes, Natural selection is natures way of making the fittest and top dogs of the food chain, It can produce a change in individuals and populations by completely reducing or wiping out a population not fit for survival in its inviroment and can even force a change of the creature to make it able to survive.
Example: would be rabbits, a snow rabbit wouldn't survive very well in the desert and a jack rabbit wouldn't be able to survive in the cold winter due to temp and the fact that predators like wolves would be able to spot it easier from its color of its fur.
Note: Hope this helps, and I hope this is want it was asking. Good luck :)
Notice how the K and Ag are both being swapped around.
Single Replacement:
A+BX → B+AX
Double Replacement:
AX+BY → BX + AY