List four possible clues to a chemical change

Which of the following describes a spontaneous reaction?

Which of the following is an example of an exothermic reaction? silt settling out of muddy water, bubbles forming in soda, photosynthesis or fireworks

What does increase mean in science

If Earth was like a hardboiled egg, which part of Earth would the egg shell represent and why? Crust, as its depth is up to 3,000 kilometers Mantle, as its depth is up to 3,000 kilometers Mantle, as its depth is less than 100 kilometers Crust, as

Ka for acetylsalicylic acid (aspirin), hc9h7o4, is 3.00*10-4. ka for hydrocyanic acid, hcn, is 4.00*10-10. ka for benzoic acid, c6h5cooh, is 6.30*10-5. what is the formula for the strongest acid?

What is the ionic composition and osmolarity of "physiological saline" - the intravenous fluid drip you receive at a hospital?

Why do dipoles cancel out?

Match each chemical with the correct use. 1. x-ray soft tissue organs 2. reduce pain and fever 3. anesthetic 4. treat acne A. benzoyl peroxide B. nitrous oxide C. acetylsalicylic acid D. barium

What subatomic particles do the following symbols represent in the atomic diagrams

2. You have 2 m3 of a mineral ore sample. It has a mass of 1 * 104 kg. Calculate the density of the ore sample and express your results in g/cm3 with appropriate scientific notation.