Answer:
Dunes are loose sand hills.
Loess is a compacted wind-blown formation of sediment.
Explanation:
Sand dunes are, as their name implies, made of sand which is itself made of tiny quartz pieces. Sand dunes are present where there is a ready source of broken down sandstone or other type of rock and wind to transport the sand. The dunes are mobile and loose and migrate over time.
Loess comes in vast formations and was created in a very different way. In the last ice age, winds from the north carried sediments loosened and ground by glaciers southwards. There, the sediments accumulated in large formations and became compacted over time.
Water and hydrogen peroxide are different compounds although they have the same kind of atoms. The molecular formula of water is H2O (two atoms of oxygen chemically bonded to one atom of oxygen). The molecular formula of hydrogen peroxide is H2O2, (each atom of oxygen is chemical bonded to one atom of H and other atom of O). So,<span> the presence of different chemical bonds leads to different products with different chemical properties.</span><span />
The eletron pairs repel each other in a tetrahedral shape.