Read the following descriptions of the element zinc and indicate which are physical properties and which are chemical properties. drag the items into the appropriate bins. reset zinc has a hardness on the mohs scale of 2.5 and a density of 7.13 g/cm3 at 25 c. zinc melts at 420 c. when zinc granules are added to dilute sulfuric acid, hydrogen is given off and the metal dissolves. it reacts slowly with oxygen gas at elevated temperatures to form zinc oxide, zno. physical properties chemical properties

Explanation:

A property that does not bring any change in chemical composition of a substance are known as physical properties.

For example, shape, size, mass, volume, density, hardness etc of a substance are all physical properties.

On the other hand, a property that changes chemical composition of a substance is known as chemical property.

For example, precipitation, reactivity, toxicity etc are chemical property.

Therefore, given descriptions are separated according to their physical and chemical properties as follows.

Physical properties:

Chemical properties:

answer: enthalpy

explanation:

for a exothermic reaction, the energy is released i.e. the energy of the products is lower than the energy of the reactants.

= enthaply

= energy of products

= energy of reactants

as , thus comes out to be negative. negative value of enthalpy shows that the reaction is exothermic.