Mass= number of mole *Molar mass
mass =2.92 mol*87.62 g/mol≈256 g
Answer:
270 Joules
Explanation:
The specific heat capacity equation will be used for this question i.e.
Q = m. c. ΔT
Where; Q = Amount of heat
m = mass of substance
C = specific heat capacity of
substance
ΔT = change in temperature
(Final temp - initial temp)
However, for this unknown metal, we need to find the specific heat first by saying; C = Q / mΔT
Q= 135J, C=?, m= 10g, ΔT = (40-25 = 15°C)
C = 135 / 15 × 10
C = 135/150
C = 0.9 J/g°C
If the specific heat capacity of the unknown metal is 0.9 J/g°C, then at a mass of 20.0g, and a ΔT of 15°C, the amount of heat needed is:
Q = m. c. ΔT
Q = 20 × 0.9 × (40-25)
Q = 18 × 15
Q = 270J
270 Joules of heat is needed to increase the temperature of 20g of the metal from 25 - 40°C
Answer:
The sun would appear to move more slowly across Mercury's sky.
Explanation:
This is because, the time it takes to do one spin or revolution on Mercury is 176 days (which is its period), whereas, the time it takes to do one spin or revolution on the Earth is 1 day.
Since the angular speed ω = 2π/T where T = period
So on Mercury, T' = 176days = 176 days × 24 hr/day × 60 min/hr × 60 s/min = 15,206,400 s
So, ω' = 2π/T'
= 2π/15,206,400 s
= 4.132 × 10⁻⁷ rad/s
So on Earth, T" = 1 day = 1 day × 24 hr/day × 60 min/hr × 60 s/min = 86,400 s
So, ω" = 2π/T"
= 2π/86,400 s
= 7.272 × 10⁻⁵ rad/s
Since ω' = 4.132 × 10⁻⁷ rad/s << ω" = 7.272 × 10⁻⁵ rad/s, <u>the sun would appear to move more slowly across Mercury's sky.</u>
Answer: 6.71 g
Explanation: 
Limiting reagent is the reagent which limits the formation of product. Excess reagent is one which is in excess and thus remains unreacted.
Thus lithium is the limiting reagent and nitrogen is the excess reagent.
As can be seen from the balanced chemical equation, 6 moles of lithium reacts with 1 mole of nitrogen to give 2 moles of lithium nitride.
Thus 0.578 moles of lithium react with 0.096 moles of nitrogen.
6 moles of lithium give = 2 moles of lithium nitride
Thus 0.578 moles of lithium give=
of lithium nitride.
Mass of lithium nitride 
Mass of lithium nitride
=
from ICE table
H2(g) + I2 (g )↔ 2HI(g)
equ 0.958 0.877 0.02 first mix1
0.621 0.621 0.101 sec mix2
Kp1 = P(HI)^2 / p(H2)*p(I2) for mix 1
= 0.02^2 / 0.958*0.877
= 4.8x10^-4
Kp2 = P(HI)^2 / P(H2)* P(I2) for mix 2
= 0.101^2/ 0.621*0.621
= 0.0265
we can see that Kp1< Kp2 that means that the sec mixture is not at equilibrium. It will go left to reduce its products and increase reactant to reduce the Kp value to achieve equilibrium.
and the partial pressure of Hi when mix 2 reach equilibrium is:
4.8x10^-4 = P(Hi)^2 / (0.621*0.621)
∴ P(Hi) at equilibrium = 0.0136 atm
