Answer:
T2 =21.52°C
Explanation:
Given data:
Specific heat capacity of sample = 1.1 J/g.°C
Mass of sample = 385 g
Initial temperature = 19.5°C
Heat absorbed = 885 J
Solution:
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 = Final temperature - initial temperature
885J = 385 g× 1.1 J/g.°C×(T2 - 19.5°C )
885 J = 423.5 J/°C× (T2 - 19.5°C )
885 J / 423.5 J/°C = (T2 - 19.5°C )
2.02°C = (T2 - 19.5°C )
T2 = 2.02°C + 19.5°C
T2 =21.52°C
NaH(s)+ H2O (l)=>NaOH(aq)+H2(g)
You want to calculate the mass of NaH, I assume. Otherwise, the question isn't clear. It simply says calculate the mass(??)
So, calculate the moles of H2 gas that satisfy the conditions of 982 ml at 28ºC and 765 torr. But you must subtract the vapor pressure of water at 28º to get the actual pressure of the H2 gas. So, the actual conditions are 982 ml (0.982 L) and 301 K and 765-28 = 737 torr.
PV = nRT
n = PV/RT = (737 torr)(0.982 L)/(62.4 L-torr/Kmol)(301 K)
n = 0.0385 moles H2
moles NaH needed = 0.0385 moles H2 x 1 mole NaH/mole H2 = 0.0385 moles NaH required
mass of NaH needed = 0.0385 moles x 24 g/mole = 0.925 g NaH
Brainliest Please :)
Answer is <span>C: It's appearance changed.</span>
Answer:
2.82 L
T₁ = 303 K
T₂ = 263 K
The final volume is smaller.
Explanation:
Step 1: Given data
- Initial temperature (T₁): 30 °C
- Initial volume (V₁): 3.25 L
- Final temperature (T₂): -10 °C
Step 2: Convert the temperatures to Kelvin
We will use the following expression.
K = °C + 273.15
T₁: K = 30°C + 273.15 = 303 K
T₂: K = -10°C + 273.15 = 263 K
Step 3: Calculate the final volume of the balloon
Assuming constant pressure and ideal behavior, we can calculate the final volume using Charles' law. Since the temperature is smaller, the volume must be smaller as well.
V₁/T₁ = V₂/T₂
V₂ = V₁ × T₂/T₁
V₂ = 3.25 L × 263 K/303 K = 2.82 L
Answer:
the number of neutrons in above isotope = A - Z = 27 - 13 = 14. Note: The molar mass of aluminium, which is average of atomic masses of all isotopes = 26.981538 g/mol, since 13Al27 is the major isotope.
Explanation:
