HELP. Which observation is a sign of a chemical change?

Main expenses you plan on making payments on a new car too. you want to spend 15% of your monthly net pay on the car payment, insurance, registration, and taxes combined. what is your monthly car allowance? $149.46 $298.91 $448.37 $597.83

How many liters of 3.0 m naoh solution will react with 0.60 liters of 4.0 m h2so4? h2so4 + naoh → na2so4 + h2o 1.2 l 1.6 l 2.4 l 2.8 l

If an atom has 12 protons and 13 neutrons