I might not be right but I think the empirical formula is NO2
Balanced equation is
HBr + NaOH ----> NaBr + H2O
Using molar masses
80.912 g HBr reacts with 39.997 g of Naoh to give 18.007 g water
so 1 gram of NaOH reacts with 2.023 g of HBR
and 5.7 reacts with 11.531 g HBr so we have excess HBr in this reaction
Mass of water produced = (5.7 * 18.007 / 39.997 = 2.6 g to 2 sig figs
Answer:
This is the first answer,
winter solstice
The winter solstice occurs during the hemisphere's winter. In the Northern Hemisphere, this is the December solstice (usually December 21 or 22) and in the Southern Hemisphere, this is the June solstice (usually June 20 or 21).
and this is the second one,
the tilt of the Earth on its axis
Seasons change because of the tilt of the Earth and the planet's movement around the Sun. Did you know? It takes about 365.25 days for the Earth to orbit the Sun. We have leap years to make up for the extra ¼ day!