Answer:
The four quantum number for each electron will be:
Explanation:
As the element is neutral, the number of protons will be equal to number of electrons which will be the atomic number of the element.
Number of electrons =12
Atomic number = 12
Element : Magnesium
The principal shell is represented by "n"
i) For "s" subshell the value of l =0 (azimuthal quantum number) thus m (magnetic quantum number)= 0
The two electrons in s subshell will have either plus half or minus half spin quantum number
ii) for "p" subshell the value for l =1
thus m = 0 or +1 or -1
The two electrons in each orbital will have either plus half or minus half spin quantum number
Answer: There are five signs of chemical change
- Color Change
- Production of an odor
- Change of Temperature
- Evolution of Gas (bubbles start to form)
- Precipitate (starts to form a solid)
When these signs start to form you know chemical change is at work.
Hope this helps :)
Answer:
1. 9.57 × 10^-9 moles.
2. 7.38mol
Explanation:
1.) To find the number of moles there are in the number of particles in an atom, we divide the number of particles (nA) by Avagadro's constant (6.02 × 10^23)
Hence, to find the number of moles (n) of Manganese (Mn), we say:
5.76 x 10^15 atoms ÷ 6.02 × 10^23
5.76/6.02 × 10^(15-23)
= 0.957 × 10^-8
= 9.57 × 10^-9 moles.
2.) Mole = mass/molar mass
Molar mass of sodium chloride (NaCl) = 23 + 35.5
= 58.5g/mol
mole = 431.6 g ÷ 58.5g/mol
mole = 7.38mol
M = n/V
.5M = n/.100 L
n = .1 L * .5M
n= .05 mols of MgCl2
mass of MgCl2 = .05 mols of MgCl2 * 95.211 grams/ 1 mol of MgCl2
mass of MgCl2 = 4.76 grams
4.76 grams of MgCl2 is needed to make 100 ml of a solution that is .500M, in chloride ion. Bolded = confused
Answer:
Tyre
In cold weather, you might have regularly kept a check on the pressure of the tyres of your car. Driving increases the temperature of the tyres, and, therefore, the air inside the tyre warms and expands. When you measure the pressure of the tyres at the time when you have just driven the car, it will be high. However, in cold weather, the pressure of the tyres will be low. So, it is recommended that you should always measure the pressure of the tyres.
