Well first we can say that B. and D. are out BC they are physical changes we are looking for chemical changes when burning gas, the gas is burning and converting into heat energy AKA FIRE!!!. so the answer is indeed (A. <span>Chemical bonds are broken and others are formed.)
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<span />BTW im not a girl every one ask that. the girls in the pic is my GF
any ways i hope you can learn something new from this. :) <3 have any amazing day
Answer:
5
Explanation:
They have 5 in common but different x
Answer:
It is already balanced equation
Answer: Lanthanide and actinide series
Explanation: The elements with partially or fully filled f orbitals belong to f block elements.
f block elements include lanthanides and actinides. They are called so the lanthanides contain the first element named as lanthanum and actinides contain first element named as actinium. They are also called as inner transition elements.
All of them have general electronic configuration:
, where n = 6-7