Answer : The mass of oxygen formed must be 3.8 grams.
Explanation :
Law of conservation of mass : It states that mass can neither be created nor be destroyed but it can only be transformed from one form to another form.
This also means that total mass on the reactant side must be equal to the total mass on the product side.
The balanced chemical reaction will be,
According to the law of conservation of mass,
Total mass of reactant side = Total mass of product side
Total mass of 
= Total mass of 
As we are given :
The mass of 
= 25.3 grams
The mass of 
= 23.4 grams
So,
Therefore, the mass of oxygen formed must be 3.8 grams.
Reactivity of Group 1 and 2 elements increases as you go down the periodic table. So sodium is more reactive than lithium. Sodium will react with oxygen forming Na2O (sodium oxide). Lithium forms lithium oxide (Li2O).
Hello there!
Sedimentary rocks are formed due to layers so the answer is A.
Best wishes
-HuronGirl
Answer is: Allena is correct. It is an element because it is only made of chlorine atoms.
A chemical element bonded to an identical chemical element is not a chemical compound since it is made from only one element and not from two different elements. Chlorine is molecule, but not compound.
Ice floats after it crystallizes because ITS DENSITY IS LESS THAN THAT OF WATER.
When a quantity of water is cools down by reducing its temperature, the molecules of the water lose kinetic energy and slow down in their movement. As the water is cooling down, it is volume is expanding. When the temperature reaches zero degree Celsius, the water becomes ice. At this point, the ice can float on water because its density is less than that of water; this is as a result of the spaces that now exist in the ice structure.
