Which of the following is not a clue that a chemical change has occurred?
a. change in color
b. production of a gas
c. formation of a precipitate
d. change in shape

What is lincoln's purpose in writing this speech? question 1 options: to stress the difficulties of war to honor those who died in the war to call for an end to the war to call the country to join a new war

The volume of helium in a blimp is 6.28 x 10^9 millimeters. the density of helium in the blimp is .1786 kilogram/meter^3. find the mass of the helium in the blimp.

What does a complete balanced chemical equation include? a. exothermic coefficients b. endothermic coefficients c. valence electrons d. molar coefficients