Macg73

Many thanks for your help

Hi, I need to rearrange this equation to make x the subject. 6y = 9 - 3x So far I have added 3x to both sides 6y + 3x = 9 -3x + 3x Then I have cancelled the 3x"s on the right hand side 6y + 3x = 9 Here is where i become a little stuck, I assume that I need to divide the equation by 3 to give the final result x = 2y + 3 What I am unsure of is how to limk the previous two equations, any help would be appreciated, thanks.

Hi, I am stuck on this question and would really appreciate some pointers on how to solve it, The specific heat capacity of the lava is 1600 J kg^-1 oC^1. when all the erupted lava cools from the eruption temperature of 1050 degrees Celsius to 15 degrees celsius, the heat released is 2 x 10 ^15 J. I need to calculate a value for the total mass of lava that erupted. Many thanks for any advice

Ok, thanks for all your time and help

The composition of hydrogen selenide can be determined by heating tin in a measured volume of gas. The hydrogen selenide is decomposed, producing solid tin selenide and hydrogen gas. If the temperature and pressure are unchanged, the gas volume when the decomposition is over is the same as it was to begin with. I need to work out a balanced equation for the reaction between hydrogen selenide and tin, and explain why the equation accounts for the fact that the gas volume is unchanged. So far I have H2Se + Sn = SnSe3 + H2, any help gratfully recieved.