Answer:
<em>Mg </em>(<em>s</em>) + 2<em>HCI2 </em>(<em>aq</em>) → <em>MgCI2 </em>(<em>aq</em>) + <em>H2 </em>(<em>g</em>)
I think this is the correct answer I not a 100% sure if it is correct.
Explanation:
Guessing
The answer is b because if you’re fan is blowing and you spend it the opposite way, the air will be cooler
They will attract each other when brought close but when they touch the glass rod will become a negative charge and will repel each other
Answer:
option A= Physical change
Explanation:
physical change:
" It is a change in which no new substance is formed"
Breaking of object like glass is the example of physical change because it is not change into another object. It effect the form of object but can not change the chemical composition.
Chemical changes:
" it is a change in which one substance is converted into new product through chemical reaction".
During the chemical changes the types and the number of atom remain same but their arrangement changed.
for example: burning of wood, baking of cake, digesting food, resting of iron etc.
Physical reaction:
" physical reaction occur during the molecular rearrangement. There is no chemical change occur"
In this type of changes no bonds are break to form new bonds, for example boiling point.
Chemical reaction:
" chemical reaction occur when molecules are chemically react with each others and bonds formation and breaking is also occur"
Explanation:
Zn=65
Cl2= 35+35=70
65+70=135g
1 mole ZnCl2 = 135g
x mole = 17.5g
17.5g × 1 mole/ 135g= 0.129 moles en 17.5g de ZnCl2
