In order to survive, plants absorb sunlight, water, and nutrients from the soil. 1. Does this represent a physical or chemical change? 2. Justify why this is this type of change. What property is this?

1) Chemical

> physical changes involves matter undergoing changes of state (solid, liquid, gas)
> chemical changes involve changing the chemical identity of the molecule (a new product is formed)

For example, if I snap a pencil in half, it is still a pencil. This is a physical change. Conversely, if I set a pencil on fire it becomes ash- a new product with different properties.

Chemical changes can be written as a chemical equation. Here is the basic (unbalanced) chemical equation for photosynthesis:

H2O+ CO2+ light (energy/ATP)-> C6H12O6+ O2

On the left of the arrow, we have our reactants (substances consumed by the reaction to make products)
On the right of the arrow, we have our products (substance formed by the chemical reaction)
Here, we see the conversation of H2O, CO2, and sunlight to sugar (C6H12O6) and oxygen. This process involves the change of chemical identity (the properties a chemical may possess- chemical bonds, stability, reactivity, etc.).
Water is not the same as sugar, both have different amount of bonds and therefore different properties. We are able to get more energy from sugar than water, which is why plants cannot survive without light. Furthermore, it is also why we cannot survive without food for too long- our bodies require a lot of energy.

2) this is a change bc the new substances (products) tht are created (from photosynthesis) are different than the original substances (reactants) (different properties)

All the elements are arranged by melting points on the periodic table. in row they go from metals to gasses. in the row from sodium to argon, sodium is more reactive than the one on its right, magnesium.