Question

end of semester test: physical science a
classify the sentences based on the chemical reactions they describe
when a clam shell (caco₃) is heated, carbon dioxide (co₂) is given off and a white powder, calcium oxide (cao), forms.
nitrogen pentoxide (n₂o₅) is an unstable gas that changes to nitrogen dioxide (no₂) and oxygen (o₂) at room temperature.
sodium (na) reacts with chlorine (cl) to give sodium chloride (nacl).
zinc (zn) metal reacts with copper sulfate (cu₂so₄) to give zinc sulfate (znso₄) and copper (cu).
a strip of magnesium (mg) burns brightly in oxygen (o₂) to form a white powder, magnesium oxide (mgo).
on heating iron ore (fe₂o₃) with carbon (c), we get iron (fe) and carbon dioxide (co₂).
synthesis decomposition replacement

Explanation:

Synthesis reactions combine substances (e.g., Na+Cl→NaCl, Mg+O₂→MgO). Decomposition reactions break down compounds (e.g., CaCO₃→CO₂+CaO, N₂O₅→NO₂+O₂). Replacement reactions involve element displacement (e.g., Zn replaces Cu in CuSO₄, C replaces Fe in Fe₂O₃).

Answer:

Synthesis	Decomposition	Replacement