Explanation:
4. limestone heat lime + carbon dioxide
The reactants in this expression above is limestone
The products of the reaction is carbon dioxide and lime
Reactant is the species that gives the product and it is usually found on the left hand side of the expression.
The product is the substance on the right hand side of the expression that forms through the experiment.
Heat is used to facilitate the reaction.
5. An exothermic reaction is a reaction in which heat is given off.
An endothermic reaction is a reaction in which heat is absorbed in the process.
An exothermic reaction is always warmer after the reaction whereas an endothermic reaction is colder at the end of the reaction.
The scientific form is

So, the form of scientific notation is
The best way to determine the number of atoms of arsenic in the sample will be to multiply 2.3 by Avagadro's number.
This is because Avagadro's number is the number of particles one mole of any substance has, and its value is 6.02 x 10²³
If the number of moles of a substance are known, then multiplying by Avagadro's number will give the number of particles. In this case, this is 1.38 x 10²⁴.
Answer is: <span>C. propanal.
1-propanol is primary alcohol. With weak oxidizing agent primary alcohol gives aldehyde and with strong oxidizing agent primary alcohol gives carbonic acid.
</span>Oxidation of 1-propanol with <span>Na</span>₂<span>Cr</span>₂<span>O</span>₇<span> and sulfuric acid</span><span> gives propanal and o</span><span>xidation with </span>chromic acid<span> gives </span>propionic acid<span>.</span>