C. Sulfur and oxygen (non metals) forms a covalent bond while the magnesium (a metal) will react with both non metals to form an ionic bond
        
             
        
        
        
Answer:
 X = 2
Explanation:
As you know, the rate of a first-order reaction depends linearly on the concentration of a single reactant. The rate of a first-order reaction that takes the form
 
        
             
        
        
        
HNO3 + Ca —-> H2O + N20 + Ca(NO3)2
        
             
        
        
        
Acid rain falls in areas that have air pollution. (<span>Acid rain is caused by emissions of </span>sulfur dioxide<span> and </span>nitrogen oxide) 
        
             
        
        
        
<h2>The isotopes of an element all have the same __(atomic, mass) __number, but they have different __(atomic,mass)__numbers.</h2>
Explanation:
The isotopes of an element all have the same __atomic  number  __, but they have different __mass __numbers.
The isotopes have same atomic number that is :
- Same number of electrons 
 - Same number of protons 
 - same electronic configuration 
 - same valence electrons 
 - same valency 
 - same symbol 
 
The isotopes have different mass number that is :
They differ in number of neutrons .
For example : Isotopes of hydrogen are : H₁¹ , H₁² , H₁³
                        isotopes of Oxygen is : O¹⁶ , O¹⁷, O¹⁸