NO₂ is a brown gas while N₂O₄ is colorless. If heating causes a brown color to persist, then this means that heating causes the reaction to shift backwards and produce NO₂. Therefore, the reaction must be exothermic.
16 grams I think it might be it
There are four processes in water cycle. Starting from the heat from the sun is the process of evaporation.
Evaporation: In this process, light from the sun evaporate water from oceans, rivers, lakes, ice and soil into water vapor. Water vapor molecules combine to form clouds.
Condensation: In this process, water vapor from clouds cool down and turns back into liquid water in the form of water droplets. These water droplets stays in the air. Precipitation: In this process, water droplets they combine in the air, they become too heavy to stay in the air. Therefore, they fall in the form of rain, snow or other form.
Collection: In this process, water that falls as rain, snow or other form comes back in the ocean, lakes, river or any other water body. Water will also be absorbed by soil and will be collected as ground water.
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