Final answer:
The type of chemical reaction that occurred is exothermic, as heat is released to the surroundings.
Step-by-step explanation:
The type of chemical reaction that occurred in the given experiment where 10 mL of vinegar reacted with 30g of baking soda, resulting in a temperature decrease of 7°C, is exothermic reaction.
In an exothermic reaction, heat is released to the surroundings. When vinegar reacts with baking soda, it releases energy in the form of heat, causing a decrease in temperature.
An example of an exothermic reaction is the combustion of wood, where heat and light are produced.