Answer:
Explanation:
A new Material is formed.
Basically, Chemical changes differ from Physical changes because in chemical changes, Substances have the ability to become a different substance.
Example:
Water to ice is a physical change because it is still water despite being a solid from liquid.
A Magnesium strip placed in CuSO4 solution made the Mg strip turn into a new substance which is MgSO4. this is a Chemical change because Mg has now become a different substance called MgSO4.
Answer:
You will find the mass of the pan and water but if the water got to its boiling temperature that mass may be a little bit off seeing as some of it may have evaporated
Explanation:
The given data for case (1) is as follows.
h = 20 cm = 0.2 m
Assuming that a rectangular slab is placed above the pipe and we will calculate the heat transfer as follows.
Q = 
where, A = area
L = length
k = thermal conductivity = 0.8 W/m
= change in temperature.
Therefore, putting the given values into the above formula as follows.
Q =
= 
= 168 W
For case (2), h = 180 cm = 1.8 m
Therefore, heat lost will be calculated as follows.
Q =
= 
= 18.67 W
Thus, we can conclude that 18.67 W heat lost if the pipe was buried at a depth of 180 cm.
D. Protons, Atomic number is the number of protons in an atom.
Answer:
9.0 moles of CaO
Explanation:
We have the reaction equation as follows;
Fe2O3 + Ca3(PO4)2 -------> 2FePO4 + 3CaO
Now we know from the equation that;
1 mole of iron III oxide yields 3 moles of CaO
Therefore;
3 moles of iron III oxide yields 3 * 3/1
= 9.0 moles of CaO
