What is the only sure evidence for a chemical reaction?

I don't know how to do this chemistry assessment over empirical formula

Complete combustion of 2.30 g of a hydrocarbon produced 7.39 g of CO2 and 2.52 g of H2O. What is the empirical formula for the hydrocarbon? Insert subscripts as necessary.

Types of fossil fuels include: hydrogen oil carbon dioxide wind coal natural gas ammonia (mark all answers that apply)

Predict how the gene pool will change over time Darwin's Natural selection sheet.

How does mass defect relate to binding energy in the nucleus? A. They both represent uncertainty in mass and energy measurements. B. The mass defect represents the mass converted to binding energy C.

Reaction rates are affected by how often the particles collide true false

A 25 N and 5 N force pull to the right. Friction is 10 N. If the object is 5 kg, find the net force and acceleration.

What properties of matter are intensive independent of their size

What is the density of an object having a mass of 8.0g and a volume of 25cm3

What is a Cilla? (In drawing)