An atom is electrically neutral when it has no extra electrons in its valence shell. the number of electrons equals the number of neutrons. the number of electrons equals the number of protons. the numbers of its protons, electrons, and neutrons are all equal. the number of protons equals the number of neutrons.

Acalorimeter is to be calibrated: 51.203 g of water at 55.2 degree c is added to a calorimeter containing 49.783 g of water at 23.5c. after stirring and waiting for the system to equilibrate, the final temperature reached is 37.6 degree c. specific heat capacity of water (s = 4.18 j/g∙degree c). calculate the calorimeter constant. (smδt)warm water = -[(smδt)cold water + (calorimeterδtcold water)]