Answer:
moles Ar in 20g = 0.500 mole Ar
Explanation:
moles = grams given / formula weight = 20g / 39.948g·mol⁻¹ = 0.500 mole Ar
Answer:
1.7x10^8 Hz
Explanation:
Frequency could be explained as the number of occurrences of a repeating event at a time
Given:
wavelength = 1.8 meters
The frequency f of the waves can be calculated using f = c / λ
Where c (m/s) is the speed of the wave
λ (m) is the wavelength
Speed c= 3*10^8 m/s
Frequency f= 3*10^8 /1.8
Frequency= 1.7x10^8 Hz
Therefore,the frequency of waves from a radar detector is 1.7x10^8 Hz
Answer:
We'll have 82 moles ZnO and 41 moles S
Explanation:
Step 1: data given
Number of moles Zinc (Zn) = 82 moles
Number of moles sulfur oxide (SO2) = 42 moles
Step 2: The balanced equation
2Zn + SO2 → 2ZnO + S
Step 3: Calculate the limiting reactant
For 2 moles Zinc we need 1 mol sulfur oxide to produce 2 moles zinc oxide and 1 mol sulfur
Zinc is the limiting reactant. It will completely be consume (82 moles). Sulfur oxide is in excess. There will react 82/2 = 41 moles
There will remain 42-41 = 1 mol SO2
Step 4: Calculate moles of products
For 2 moles Zinc we need 1 mol sulfur oxide to produce 2 moles zinc oxide and 1 mol sulfur
For 82 moles Zinc we'll have 82 moles of Zinc Oxide (ZnO)
For 82 moles Zinc we'll have 82/2 = 41 moles of sulfur
We'll have 82 moles ZnO and 41 moles S
It is called boiling when evaporation takes place beneath the surface of a liquid. The evaporation is a kind of vaporization only takes place at the surface of a liquid.
Answer:
The amount of heat that is released is -925.2 cal
Explanation:
Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
Sensible heat is the amount of heat that a body can receive or release without affecting its molecular structure, that is, it does not change the state (solid, liquid, gaseous). In other words, sensible heat is the amount of heat that a body absorbs or releases without any changes in its physical state.
The equation that allows to calculate heat exchanges is:
Q = c * m * ΔT
Where Q is the heat exchanged by a body of mass m, constituted by a substance of specific heat c and where ΔT is the variation in temperature.
In this case:
- c= 1
- m= 25.7 g
- ΔT= Tfinal - Tinitial= 49 °C - 85 °C= -36 °C
Replacing:
Q= 1 *25.7 g* (-36 C)
Solving:
Q= -925.2 cal
<u><em>The amount of heat that is released is -925.2 cal</em></u>
