If a valence electron doesn’t gain or lose electrons what is the charge

Chris is about to do an experiment to measure the density of water at several temperatures. his teacher has him prepare and sign a safety contract before beginning the experiment. which term is mostlikely part of the safety contract

The table below shows the freezing points of four substances. substance freezing point (°c) benzene 5.5 water 0 butane –138 nitrogen –210 the substances are placed in separate containers at room temperature, and each container is gradually cooled. which of these substances will solidify before the temperature reaches 0°c? benzene water butane nitrogen

You form water vapor by mixing oxygen and hydrogen at 730°c in a 5.4-liter container. this is the equation for the reaction: o2(g) + 2h2(g) → 2h2o(g). the partial pressure of oxygen before the reaction is 122.3 kilopascals, and there is excess hydrogen. how many moles of water are formed?