Why is it more difficult to prove a correct theory than to disprove an incorrect one

Which of these processes indicates that smelting copper is a chemical change a) it involves melting copper to form liquid metal b) it involves heating charcoal to high tempuratures c) it involves drawing copper into long wires d) it involves

Balanced chemical equation for the standard formation reaction of solid sodium carbonate

A scientist finds a fossil that contains a long beak. He can assume which of the following things?

How does the arrangement of elements in periods relate to electron configuration

A gas occupies 12.3 liters at a pressure of 40.0 mm Hg. What is the volume when the pressure is increased to 60.0 mm Hg?

1. Bubbling or fizzing is an indicator of a. property change b. phase change c. physical change d. chemical change

In the second step of this reaction, isocyanic acid reacts to form melamine and carbon dioxide: HNCO (l) →C3N3 (NH2) 3 (l) + CO2 (g) Balance this reaction and enter the coefficients below.

If the Kelvin temperature of a gas is tripled and the volume if doubled, the new pressure will be ___. A. 3/2 the original pressure B. 1/6 the original pressure C. 5 times the original pressure D. 2/3 the original pressure the answer isnt b or c

To squeeze gas into a smaller space

What kind of solution would have a Kb value much greater than 1? A. a weakly acidic solution B. a strongly basic solution C. A strongly acidic solution D. A weakly basic solution