Answer:
10. Stacey
11. 7.86 g/cm^3 (3dp)
OR 786 kg/m^3 (SI units)
Explanation:
10. The correct exact answer for 10 is 26.169 (6.71x3.9). While Sam was correct in the precision of the number (2dp just like the given measurements), he was incorrect in the number itself. While Stacy's number was not as precise as Sam's (0dp), it is correctly rounded to the nearest whole number, therefore Stacy is correct.
11. The formula for density is mass/volume. The mass here is 264g and the volume is 33.6ml, therefore the density is 7.86 (3 sig figs because given values had 3) g/cm^3, because the mass was given in grams and 1ml = 1cm^3. Converted to SI units it is 786 kg/m^3.
Hope this helped!
Answer:
c = 0.528 J/g.°C
Explanation:
Given data:
Mass of titanium = 43.56 g
Heat absorbed = 0.476 KJ = 476 j
Initial temperature = 20.5°C
Final temperature = 41.2°C
Specific heat capacity = ?
Solution:
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
ΔT = 41.2°C - 20.5°C
ΔT = 20.7 °C
476 J = 43.56 g × c × 20.7 °C
476 J = 901.692 g.°C × c
c = 476 J / 901.692 g.°C
c = 0.528 J/g.°C
Answer:
See explanation
Explanation:
The drug thalidomide with molecular formula C13H10N2O4 was widely prescribed by doctors for morning sickness in pregnant women in the 1960s.
The drug was sold as a racemic mixture (+)(R)-thalidomide and (-)(S)-thalidomide.
Unfortunately, only the (+)(R)-thalidomide exhibited the required effect while (-)(S)-thalidomide is a teratogen.
This goes a long way to underscore the importance of separation of enantiomers in drug production.
Therefore, all the teratogenic effects observed when using the drug thalidomide was actually as a result of the presence of (-)(S)-thalidomide, the unwanted enantiomer.
V = f 入 (velocity = frequency x wavelength)
<span>If we have the speed ( for wave in vacuum </span><span>i.e. 3 x 10^8 m/s) </span>
<span>Then the frequency of x-ray is </span>
<span>(3 x 10^8) ÷(1.15 x 10^-10) = 2.61 x 10^18 </span>
Answer;
= 18.24
Explanation;
The ratio of N and O in the formula NO2 IS 1:2
Mass of nitrogen gas is 0.500 g
Moles of nitrogen will be;
= 0.500/16 = 0.03125 moles
Therefore;
The moles of Oxygen from the ratio will be;
= 0.03125 × 2 = 0.0625 moles
But; 0.0625 moles is equal to 1.140 g of Oxygen
The atomic number (mass in 1 mole) will be;
= 1.140 /0.0625
= 18.24
Thus the atomic number of Oxygen from the data is 18.24
