Which substance has one proton and one neutron?
a. h-1
b. h-2
c. he-1
d. he-2

Modern weaponry has increased the number of deaths in wars and violent conflicts.

When the chemicals iron sulfide (fes) and hydrochloric acid (hcl) are combined, bubbles appear from the mixture. 1. does the appearance of bubbles indicate a physical or chemical change? 2. why do the bubbles indicate this change? 3. what property is this?

11) burning your hand when accidentally touching a hot plate is an example of which heat transfer? a. conduction b. convection c. radiation d. none of these