# What is the characteristic of matter that causes it to expand when the temperature increases and contract when the temperature decreases?a. gas law b. collision theory c. thermal expansion d. phase

Posted on

We can consider thermal expansion as the answer among the following since according to thermal expansion with change in temperature there is change is characteristic of matter in length wise, area wise and also volume wise. Increased temperature helps in breaking the bond energy and helps in expansion which lead to linear expansion, areal expansion and also expansion in volume. When temperature is decreased the bonds between the atoms contract which leads to change in characteristic of matter. Thermal expansion also explains about the hardness of the matter, if thermal expansion is less than the substance is harder and vise versa.

Posted on

According to gas laws there is a common formula that is

PV = nRT

Which explains that with increase in temperature the volume of matter increases and with decrease in temperature volume decreases since volume is directly propositional to temperature this was explained by Charles's law. Example In parachute volume increases and balloon expands with increase in temperature.

According to collision theroy the reaction molecule must collide with each other and must collide with sufficient energy to break bonds and convert into products. With increase in temperature number of collisions increases and the molecules will have sufficient energy to break bond and convert into products.

According to thermal expansion with increase in temperature there is expansion of length, area and volume of matter. Thermal expansion also explains hardness of matter, substance which are harder will have high bond energy and low thermal expansion. With increase in temperature matter expands and with decrease in temperature it will contract which inturn depends on the bond energy of matter.

A phase is refered as state of matter there are three state of matter they are solid, liquid and gases. With increase in temperature the state of matter changes from solid to liquid which is called as melting and volume increases. With further increase in temperature liquid changes to gas phase which is called as evaporation and volume increase. With decrease in temperature condensation takes place followed by solidification and volume also decrease.

In all these theory charles law is followed that is volume is directly propostional to temperature.

Sources: