Answer:
Platinum Gold and silver are used to make jewellery because of the following reasons. They are highly lustrous metals which are resistant to corrosion. They are highly malleable and ductile so can be transformed into any shape or design.
Explanation:
These animals are all invertebrates
An element or compound which occurs naturally in the earth is a mineral
Answer: The number to the left of AC should be 6.
Explanation: The balanced chemical reaction is one in which the number of atoms of each element on the reactant side must be equal to the number of atoms on product side.
The given equation 
is unbalanced as the atoms on the reactant side are not same as number of atoms on product side. This equation is called as skeletal equation.
The balanced chemical equation is :
Thus the number to the left of AC is 6.
Answer:
The empirical formula is the simplest ratio of atoms while molecular is the actual formula.
Explanation:
Empirical Formula is the simplest ratio of atoms present in the compound.
The molecular formula shows the actual number of atoms present in the compound.
For example, CH is the empirical formula and C6H6 is the molecular formula of benzene.
