Answer : The mass of
needed are, 1.515 grams.
Explanation :
First we have to calculate the mole of
.

Now we have to calculate the moles of
.
The balanced chemical reaction will be,
produced from 1 mole of 
So, 0.005 mole of
produced from 0.005 mole of 
Now we have to calculate the mass of 


Therefore, the mass of
needed are, 1.515 grams.
Answer:
Magnesium and calcium belong to the second group i. e. alkaline earth metals. They are known as earth metals because they are extracted from the earth. They are very reactive elements. Their reactivity increases when we go from top to bottom because the outermost electrons goes farther from the nucleus i. e. atomic radius increases so less energy is needed for its removal.
The answer is the second choice.
Explanation:
Physical change -
It refers to any change during any process , where there is no new substance is formed , is referred to as a physical change.
Any change in the state of matter is characterised under physical change.
Chemical change -
It refers to any change in a chemical process , where there is formation of any new substance , is referred to as a chemical change .
From the options given in the question,
1. Apple turning brown , on air exposure , is an example of chemical change .
2. The physical state of mercury is liquid , is an example of physical change .
3. phosphorus burns on exposed to air , is an example of chemical change .
4. The gas Neon is colorless at the room temperature , is is an example of physical change .
Answer:
The Moon's surface is dominated by igneous rocks. The lunar highlands are formed of anorthosite, an igneous rock predominantly of calcium-rich plagioclase feldspar
Explanation: