Which of the following is a chemical change
a. melting ice
b. boiling water
c. a burning candle
d. frost formingg inside freezer

Calculate the expected ph values of the buffer systems from the experiments (a, b,c, d), using the henderson- hasselbalch equation, ph-pka+log[a-]/[ha]. use for pka values carbonic acid= 6.37, and acetic acid= 4.75.

Which activity describes an application of topographic maps? check all that apply. recreation, such as camping and hiking engineering, such as the construction of roads and buildings science, such as mapping stars in the sky business, such as analyzing population centers science, such as analyzing surface features

Spaghetti sauce can be high in sodium. what is a good guideline for mg of sodium per half cup serving? a. less than 1 mg b. less than 800 mg c. less than 700 mg d. less than 400 mg