A chemical change results in a change in chemical composition of the substances involved.
O sometimes
Orarely
O always
O never

Is the following sentence true or false? Chemical properties are observed only when a substance undergoes a chemical change.

O true
O false

prove evidence also if you can, thanks .

In order to calculate the amount of heat transferred you must know the __ and specific heat of the material, as well as the change in temperature. a. volume b. density c. mass d. enthalpy

Will give brainliest it is a lab from k12 here is the linkfor each metal that participated in a chemical change, write the type of metal it is, based on your examination of the periodic table. type your answer here. (score for question 3: of 5 points) were there any metallic compounds that did not react with either the acid or the base? write the type of metal, based on your examination of the periodic table. type your answer here. (score for question 4: of 5 points) make a general statement about the reactivity of the metals in this experiment. type your answer here.

What is the typical rotational frequency frot for a molecule like n2 at room temperature (25∘c)? assume that d for this molecule is 1å=10−10m. take the total mass of an n2 molecule to be mn2=4.65×10−26kg. you will need to account for rotations around two axes (not just one) to find the correct frequency. express frot numerically in hertz, to three significant figures.