Question

a reaction where two or more substances combine to form one compound 5 points is: a + b → ab single replacement double replacement synthesis reaction decomposition the law of conservation of matter helps chemists: 5 points change atoms into new types measure energy release only predict mass loss during reactions balance equations by ensuring equal numbers of each atom type

Explanation:

• First question: A synthesis reaction is defined as a reaction where two or more substances combine to form one compound. In the given diagram \(A + B

ightarrow AB\), two substances \(A\) and \(B\) combine to form a single compound \(AB\). A single - replacement reaction has the form \(A+BC
ightarrow AC + B\), a double - replacement reaction has the form \(AB+CD
ightarrow AD + CB\), and a decomposition reaction has the form \(AB
ightarrow A + B\).

• Second question: The Law of Conservation of Matter states that matter is neither created nor destroyed in a chemical reaction. Chemists use this law to balance chemical equations. By ensuring that the number of each type of atom is the same on both sides of the equation (e.g., if there are 2 hydrogen atoms on the reactant side, there must be 2 hydrogen atoms on the product side), they are applying the Law of Conservation of Matter. Atoms are not changed into new types (that would be nuclear reactions, not chemical reactions), the law is not just about energy release (which is more related to thermodynamics), and there is no mass loss in a chemical reaction according to the law (mass is conserved).

Answer:

• First question: Synthesis reaction
• Second question: Balance equations by ensuring equal numbers of each atom type