Answer:
A molecule is a bunch of atoms combined.
An atom is the smallest part of an element, that you can get without splitting the nucleus of the atom.
Molecules are made of more two or more atoms joined together. The atoms can be same or different elements. A single molecule is the smallest piece of matter you can have without changing its properties.
Explanation:
Answer: Option C) 4 moles
Explanation:
The reaction below shows the decomposition of 2 moles of water to yeild 2 moles of hydrogen and 1 mole of oxygen respectively.
2H2O(l) --> 2H2(g) + O2 (g)
So, if 2 moles of H2O produce 1 mole of O2
8 moles of H2O will produce Z mole of O2
To get the value of Z, cross multiply
2 x Z = 1 x 8
2Z = 8
Z = 8/2
Z = 4
Thus, 4 moles of O2 is produced from the complete decomposition of 8 moles H2O .
This question refers to significant figures. The reason we follow significant figure rules when performing calculations in science is that a calculated answer (which is an extrapolation of a manipulation of measurements) can only be as precise as the least precise measurement recorded. This means if you record measurements to a certain precision, the calculated answer at the most can only match the recorded level of precision as to balance the level of confidence in accuracy before and after calculations.
Explanation:
The nomenclature of ionic compounds is given by:
1. Positive is written first. And if the metal atom has various oxidation states then its oxidation state is to be mentioned in brackets with help of roman numbers
2. The negative ion is written next and a suffix is added at the end of the negative ion. The suffix written is '-ide'.
1.) : Calcium chloride (Correct)
In the given compound, calcium has oxidation state of +2 and chlorine has oxidation state of -1.The name is correct.
2.) : Copper (II) oxide (Incorrect)
In the given compound,copper has the oxidation state of +1 and oxygen has oxidation state of -2.So ,the correct name will be Copper (I) oxide.
3.) : Lead (II) sulfide (Incorrect)
In the given compound, lead has the oxidation state of +4 and sulfur has oxidation state of -2. So ,the correct name will be Lead (IV) sulfide.