Qualification > Sciences
CHEMISTRY PAPER 1 HERE
aquarian93:
--- Quote from: i-insane on June 11, 2009, 02:44:24 pm ---
--- Quote from: aquarian93 on June 11, 2009, 02:42:13 pm ---this is from may 05, if anyone has solved it, pls help me.
for question 16, the answer is D
y cnt it b C? pls help, thanks in advance
--- End quote ---
For 3, there would be no loss in mass, as any gas produced would remain inside the conical flask, and not be able to excape through the stopper.
--- End quote ---
yea bt if it dusnt escape, u can still use it cuz the mass will increase as gas is produced and wont escape. da mass will increase
rite?
esso:
its neutrilisation rite....cause hydrogen is removed from acids when reacting with bases
nid404:
--- Quote from: dondon93 on June 11, 2009, 02:47:33 pm ---Guys please help with this,...
When lithium reacts with water, if forms lithium oxide + hydrogen OR it forms lithium hydroxide + hydrogen????
And which metals react with water to form metal oxide + hydrogen and which ones react with water to form metal hydroxide + hydrogen???
Help please???
--- End quote ---
Lithium is a group 1 metal so it forms hydroxide and hydrogen
Group 2 metals react to form metal oxide and hydrogen(but magnesium reacts with steam to give hydroxide
Metals below hydrogen in reactivity do not form either.
girl_92:
--- Quote from: aquarian93 on June 11, 2009, 02:42:13 pm ---this is from may 05, if anyone has solved it, pls help me.
for question 16, the answer is D
y cnt it b C? pls help, thanks in advance
--- End quote ---
u cannot take 3 bcoz a stopper will not allow the gas to escape n the two methods loss of mass wid time n amount of gas collected by the passage time are used in 2 n 4
....:
--- Quote from: aquarian93 on June 11, 2009, 02:49:20 pm ---
--- Quote from: i-insane on June 11, 2009, 02:44:24 pm ---
--- Quote from: aquarian93 on June 11, 2009, 02:42:13 pm ---this is from may 05, if anyone has solved it, pls help me.
for question 16, the answer is D
y cnt it b C? pls help, thanks in advance
--- End quote ---
For 3, there would be no loss in mass, as any gas produced would remain inside the conical flask, and not be able to excape through the stopper.
--- End quote ---
yea bt if it dusnt escape, u can still use it cuz the mass will increase as gas is produced and wont escape. da mass will increase
rite?
--- End quote ---
Umm no, conservation of mass = mass of products is always equal to mass of reactants. So, to show the rate of reaction, a decrease in mass must occur.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version