Answer:
a. The reaction is endothermic.
Explanation:
The heat involved in a chemical reaction is given by the enthalpy change (ΔH), which is equal to the balance between the chemical bonds that are broken (release energy) and the chemical bonds that are formed (need energy):
ΔH ≅ bonds broken - bonds formed
If broken bonds > bonds formed ⇒ ΔH > 0 ⇒ endothermic reaction
Therefore, the reaction is endothermic (it requires energy).
Answer:9.49g/mL
Explanation:
Mass of toy = 43.672g
Volume of water = 34.4mL
Volume of toy + volume of water = 39mL
Volume of toy = 39 — 34.4 = 4.6mL
Density = Mass /volume
Density = 43.672/4.6 = 9.49g/mL
Km is the biggest measure in width (even if there are bigger measures like Mm, Gm, Tm).
1 Km = 1000 m, 100000 cm and 1000000 mm
