Answer:
Number 4 is an example of a chemical reaction
Explanation:
heThe chalk is reacting with the vingear which is creating a new substance. The new substance is the gas that the reaction gives off.
Answer: False
Explanation:
Molecular formula is the chemical formula which depicts the actual number of atoms of each element present in the compound.
Empirical formula is the simplest chemical formula which depicts the whole number of atoms of each element present in the compound.
Example: 
has similar molecular formula and empirical formula as the elements are already present in simplest of the ratios.
has molecular formula of but 
as the empirical formula.
The element is Sr (strontium)
strontium is in atomic number 38 in the periodic table. Strontium has 2.8.8.8.8.2
it loses two electrons to become stable hence it has a charge of 2+. when strontium loses two electron it form ion with 36 electrons
If you are comparing 2 metals, the metal with a higher <u>Number of free ions</u> will react with EDTA first
<h3>What is EDTA ?</h3>
EDTA is a type of chemical which binds certain metal ions such as calcium and magnesium. some of the functions of EDTA includes:
- Preventing blood clotting of blood samples
- prevention of the formation of Biofilm by bacterias
The EDTA will readily react with metals which have a hiogher number of free ions that it can bind with.
Hence we can conclude that If you are comparing 2 metals, the metal with a higher <u>Number of free ions</u> will react with EDTA first.
Learn more about EDTA : brainly.com/question/10818175
