As scientists opinion is a valid source of information to use in a scientific investigation is this statement true or false ? and why

During trial 2, what allowed you to determine that aluminum was the limiting reactant? check all that apply. all of the copper dissolved. all of the aluminum dissolved. the solution turned clear. the number of grams of copper(ii) chloride used in the reaction was greater than the number of grams of aluminum. the molar ratio of copper(ii) chloride to aluminum was greater than 3: 2, the equation’s molar ratio.

Earth's axis of rotation is tilted at an angle of 23.5 degrees. what is one change you would see on earth if its axis was not tilted?

An atom of lithium-7 has an equal number of(1) electrons and neutrons(2) electrons and protons(3) positrons and neutrons(4) positrons and protons