Answer:
physical
Explanation:
The zinc (which was already silver) coated the penny. The NaOH dissolved the zinc. (that was what made the water murky) And small pieces of zinc adhered to the penny (coated) It was a physical change because no NEW color was created.
Answer:
The pressure of the gas will increase.
Explanation:
This concept of change in state properties of gas, when compressed in a moveable piston-cylinder assembly, can be explained by using Boyle's law
Boyle's law states that the pressure of a given mass of gas is inversely proportional to its volume given that temperature remains constant.
Following this law, when the gas in the container is compressed to a smaller volume, the pressure will go up.
This is also because the gas is not free to move about without frequent collisions with itself and the walls of the container, due to the resulting smaller space after compression. Therefore, the force it exerts on the walls of the container and the frequency of collision are more.
Answer:
how can I solve this ?4Al+3O2 produce 2Al2O3 find a) oxygen atoms needed to react with 5.4 g of aluminium b) grams of oxygen needed to react with 0.6 mol of aluminium?
(A) n=m/M,
n(Al)=5.4/27=0.2 moles
n(O2)=n(Al)*3/4=0.2*3/4=0.15 moles
Number of oxygen atoms= n(O2)*Avogadro's number
=0.15*6.02*10^23=9.03*10^22 oxgyen atoms
(B)
n=m/M
n(Al)=0.6/27=0.02222 moles
n(O2)=n(Al)*3/4=0.016666 moles
m=n*M
m(O2)=0.0166666*32=0.53333 grams
Answer:Do you think the climate change has only to do with human society or is it also occuring "naturally"?
I was in Germany on december of last year (2011) and I was surprised because it didn´t snow. I read about the melting of the principal glacier and it will raise the ocean water levels. There are people that blame only human being for the climate changes but I wish to know how much we are responsible for that.
Climate Change
Explanation:
Because of the fact that NaBr is an ionic bond, the bond is harder to break, therefore it needs more heat (or a higher temperature) to break it.