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few q's. (1 Viewer)

blackratpoo

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a) name the isotope that undergoes beta decay to form thorium - 227.

b) the molar heat of combustion of ethanol is 1367 kJ mol-1. what mass of ethanol is required to heat 1 mole of water by 10 degrees?
 

locked.on

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Please find the solutions attached below.

Feel free to correct me if I am wrong. Please ask me to clarify anything that you still don't understand or that I may have not explained properly.

Hope it helps.
 

blackratpoo

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wow. thanks heaps for these elaborate answers. b) is correct however the answer to a) is Actinium -227. do you think this is wrong?
 

study-freak

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a) name the isotope that undergoes beta decay to form thorium - 227.

b) the molar heat of combustion of ethanol is 1367 kJ mol-1. what mass of ethanol is required to heat 1 mole of water by 10 degrees?
wow. thanks heaps for these elaborate answers. b) is correct however the answer to a) is Actinium -227. do you think this is wrong?
The answer is correct.
Beta decay is when a neutron decays into a proton (which stays in the nucleus) and an electron (which is emitted out as a beta particle). Hence atomic number increases by one while atomic mass stays the same.
Actinium-227 decays into a beta particle and Thorium-227.
 

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