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!
To get the value of ΔG we need to get first the value of ΔG°:
when ΔG° = - R*T*㏑K
when R is constant in KJ = 0.00831 KJ
T is the temperature in Kelvin = 25+273 = 298 K
and K is the equilibrium constant = 4.5 x 10^-4
so by substitution:
∴ ΔG° = - 0.00831 * 298 K * ㏑4.5 x 10^-4
= -19 KJ
then, we can now get the value of ΔG when:
ΔG = ΔG° - RT*㏑[HNO2]/[H+][NO2]
when ΔG° = -19 KJ
and R is constant in KJ = 0.00831
and T is the temperature in Kelvin = 298 K
and [HNO2] = 0.21 m & [H+] = 5.9 x 10^-2 & [NO2-] = 6.3 x 10^-4 m
so, by substitution:
ΔG = -19 KJ - 0.00831 * 298K* ㏑(0.21/5.9x10^-2*6.3 x10^-4 )
= -40
Answer:
When bethany walks across a carpet, her socks pick up many electric charges. Later in the day, these charges are no longer present on her socks. What most likely happened to the charges.
A. the charges disappeared.
B. The charges switched signs
C. the charges transferred to another object ✓
D. The charges broke apart into smaller particles
Answer:
Explanation:
The law of multiple proportions states that if two elements X and Y combine together to form more than one compound, then the several masses of X which chemically combine with a fixed mass of Y is in simple ratio.T
FIRST CASE ;
- Molar mass of Nitrogen gas = 28 g/mol
- Number of moles of Nitrogen gas = Mass/molar mass = 3.50/28 = 0.125 moles
- Number of moles of Oxygen gas = Mass/molar mass = 2.00/32 = 0.0625 moles
- Hence the ratio of number of moles of N2 to O2 will be 0.1295 : 0.0625 or 2:1
- Similarly for the SECOND CASE ;
- Molar mass of Nitrogen gas = 28 g/mol
- Number of moles of Nitrogen gas = Mass/molar mass = 0.875/28 = 0.03125 moles
- Number of moles of Oxygen gas = Mass/molar mass = 1/32 = 0.03125 moles
- Hence the ratio of number of moles of N2 to O2 will be 0.03125 : 0.03125 or 1:1
