First, we will need to find the density of the object, take the mass and divide it by the dispplaced water:
128/424 = 0.302 grams/milliliters
Convert that to kg/m3
We get: 302kg/m3
Divide that to the density of water: 1000kg/m3
302/1000 = 0.302
(thats a pretty darn light weighted metal)
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 .
Here we have to get the spin of the other electron present in a orbital which already have an electron which has clockwise spin.
The electron will have anti-clockwise notation.
We know from the Pauli exclusion principle, no two electrons in an atom can have all the four quantum numbers i.e. principal quantum number (n), azimuthal quantum number (l), magnetic quantum number (m) and spin quantum number (s) same. The importance of the principle also restrict the possible number of electrons may be present in a particular orbital.
Let assume for an 1s orbital the possible values of four quantum numbers are n = 1, l = 0, m = 0 and s = 
.
The exclusion principle at once tells us that there may be only two unique sets of these quantum numbers:
1, 0, 0, +
and 1, 0, 0, -
.
Thus if one electron in an orbital has clockwise spin the other electron will must be have anti-clockwise spin.