Atoms have electrons filled in energy shells.
1. H - hydrogen atom has one electron in the First energy shell. Therefore hydrogen has a partially filled first energy shell
2.Li - Li electron configuration is 2,1
The outermost energy shell is the second energy shell in which there is only one electron
Therefore the second energy shell is partially filled. This is the correct answer
3. K - electron configuration is 2,8,8,1
The outermost energy shell is the fourth energy shell which is partially filled. The second energy shell is completely filled
4.Na - electron configuration is 2,8,1
The outermost energy shell is the third energy shell which is partially filled
Second energy shell is completely filled
From the given options Li is the only element with a partially filled second energy shell
Answer is Li
First find the number of moles of sulfur using dimensional analysis with avogadro’s number as the conversion factor. 4.2*10^24 atoms * (1 mol/6.022*10^23 atoms) = 7.0 mol sulfur. The molar mass of sulfur is 32.06 g/mol, which is found on the periodic table as sulfur’s (S) atomic weight. Use dimensional analysis again with the molar mass of sulfur as the conversion factor. 7.0 mol * 32.06 g/mol = 224.42 g sulfur. Since the problems gives us two significant figures, round the mass of sulfur to 220 grams, or 2.2 * 10^2 g.
Answer:
Q = 2640.96 J
Explanation:
Given data:
Mass of He gas = 10.7 g
Initial temperature = 22.1°C
Final temperature = 39.4°C
Heat absorbed = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree. Specific heat capacity of He is 14.267 J/g.°C
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 39.4°C - 22.1°C
ΔT = 17.3°C
Q = 10.7 g× 14.267 J/g.°C × 17.3°C
Q = 2640.96 J
The answer is 72973739373
The approximate alcohol content is 210 ml.
Explanation:
It can be deduced from the question that each bottle is of 1000ml or 1 litre.
The first bottle is one half full means it has 500 ml of solution and it has 20% alcohol in it. So volume of alcohol in the solution is
20/100*500
=100 ml
The first bottle is one fifth full, so the volume of mixture is 1/5th of 1000ml
so it is 200ml having 30% alcohol
30/100*200
= 60 ml
The third bottle is one tenth full so its volume is 1/10*1000
100 ml. having 50% of alcohol
50/100*100
50 ml.
The alcohol content obtained from all these 3 litres is:
100+60+50
= 210 ml of alchohol is obtained from 800 ml of mixture.
