Answer:
7 is the only basic number on a pH scale
Explanation:
When magnesium metal burns is heated i the air it forms magnesium oxide.The balanced chemical reaction is given as:

2 moles of magnesium metal when reacts with 1 moles of oxygen it gives 2 moles of magnesium oxide which is white in color.
Some times along with formation of magnesium oxide small amount of magnesium nitride also produced due to which magnesium oxide appears grey in color .The balanced chemical reaction is given as:

3 moles of magnesium combines with 1 mol of nitrogen gas to to give 1 mol of magnesium nitride.
an erosive process or erosion
erosion is when a rock is changed through the weather
Answer:
20 seconds
Explanation:
if hes travelling to get to 300 meters, you have to divide the distance(300) by time (15) to get your answer of 20 seconds
Mass
Explanation:
Mass is different from the rest based on those two categories.
Physical properties are the properties of matter that are usually determined with our senses like taste, feel, color, odor e.t.c
Chemical properties are the properties that relates to a substance when changes are occurring to it.
These properties are boiling point, magnetism and thermal conductivity among others.
Mass is not a physical nor chemical property. It is classified as an extensive property of substances which varies according to the amount of matter it contains.
Learn more:
chemical change brainly.com/question/9388643
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