Answer:
Fluorine
General Formulas and Concepts:
<u>Chemistry</u>
- Reading a Periodic Table
- Periodic Trends
- Electronegativity - the tendency for an element to attract an electron to itself
- Z-effective and Coulomb's Law, Forces of Attraction
Explanation:
The Periodic Trend for Electronegativity is up and to the right of the Periodic Table.
Fluorine is Element 9 and has 9 protons. Radium is Element 88 and has 88 protons. Therefore, Radium has a bigger Zeff than Flourine.
However, since Radium is in Period 7 while Fluorine is in Period 2, Radium has more core e⁻ than Fluorine does. This will create a much larger shielding effect, causing Radium's outermost e⁻ to have less FOA between them. Fluorine, since it has less core e⁻, the FOA between the nucleus and outershell e⁻ will be much stronger.
Therefore, Fluorine would attract an electron more than Radium, thus bringing us to the conclusion that Fluorine has a higher electronegativity.
Answer:
copper will reach to higher temperature first.
Explanation:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
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
The substances with higher value of specific heat capacity require more heat to raise the temperature by one degree as compared the substances having low value of specific heat capacity.For example,
The specific heat capacity of copper is 0.386 j/g. K and for aluminium is 0.900 j/g.K. So, aluminium take a time to increase its temperature by one degree by absorbing more heat while copper will heat up faster by absorbing less amount of heat.
Consider that both copper and aluminium have same mass of 5g and change in temperature is 15 K. Thus amount of heat thy absorbed to raise the temperature is,
For copper:
Q = m.c. ΔT
Q = 5 g× 0.386 j/g K × 15 K
Q = 28.95 j
For aluminium:
Q = m.c. ΔT
Q = 5 g× 0.900 j/g K × 15 K
Q = 67.5 j
we can observe that aluminium require more heat which is 67.5 j to increase its temperature. So it will reach to higher temperature later as compared to copper.
Answer:
sodium sulphide.
Explanation:
First, let us obtain the percentage of sulphur in both compounds. This is illustrated below:
For sodium sulphide(Na₂S):
Molar Mass of Na₂S = (23x2) + 32 = 46 + 32 = 78g/mol
Percentage of sulphur in Na₂S is given by:
32/78 x 100 = 41%
For zinc sulphide(ZnS):
Molar Mass of ZnS = 65.4 + 32 = 97.4g/mol
Percentage of sulphur in ZnS is given by:
32/97.4 x 100 = 33%
From the results obtained sulphur has the highest percentage by mass in sodium sulphide.
Answer : The work done on the surroundings is, 709.1 Joules.
Explanation :
The formula used for isothermally irreversible expansion is :
where,
w = work done
= external pressure = 1.00 atm
= initial volume of gas = 1.00 L
= final volume of gas = 8.00 L
Now put all the given values in the above formula, we get :
The work done by the system on the surroundings are, 709.1 Joules. In this, the negative sign indicates the work is done by the system on the surroundings.
Therefore, the work done on the surroundings is, 709.1 Joules.
