Explanation:
Brittleness is a characteristic that describes chalk. Its color and shape also describe the chalk. Any such characteristic of a material that you can observe without changing the substances that make up the material is a physical property
Gold is metallic, with a yellow colour when in a mass, but when finely divided it may be black, ruby, or purple. It is the most malleable and ductile metal
Answer:
Colors of transition metal compounds are due to two types of electronic transitions. Due to the presence of unpaired d electrons, transition metals can form paramagnetic compounds. Transition metals are conductors of electricity, possess high density and high melting and boiling points.
Explanation:
Answer:
The specific heat capacity of glass is 0.70J/g°C
Explanation:
Heat lost by glass = heat gained by water
Heat lost by glass = mass × specific heat capacity (c) × (final temperature - initial temperature) = 58.5×c×(91.2 - 21.7) = 4065.75c
Heat gained by water = mass × specific heat capacity × (final temperature - initial temperature) = 250×4.2×(21.7 - 19) = 2835
4065.75c = 2835
c = 2835/4065.75 = 0.70J/g°C
<span>If energy is released, the reaction is exothermic. If energy is absorbed, the reaction is endothermic. Since heat is being absorbed in this reaction (to break down H2O into H2 and O), the reaction is endothermic.</span>