Answer:
81.5g/mol
Explanation:
Molar mass is the ratio between mass of a substance (In this case, 0.207g) and moles presents in this mass.
To solve this question we must find the moles of the gas in order to obtain the molar mass using:
PV = nRT
PV / RT = n
<em>Where P is pressure = 0.980atm</em>
<em>V is volume in Liters = 0.0725L</em>
<em>R is gas constant = 0.082atmL/molK</em>
<em>T is absolute temperature = 68°C + 273.15 = 341.15K</em>
<em />
0.980atm*0.0725L / 0.082atmL/molK*341.15K = n
2.54x10⁻³ moles = n
Thus, the molar mass of the gas is:
0.207g / 2.54x10⁻³ moles
<h3>81.5g/mol</h3>
Answer:
gains two electron!
Explanation:
When a barium atom forms its most common ion, it gains two electron!
7.91 g/ml is the density of the iron piece of 28.5 gms.
Explanation:
The density of a substance is defined as the volume it occupies. It tells the matter present in a substance.
The density is mass per unit volume and is denoted by p.
The formula for density is given by:
density (p) = 
Data given is :
mass= 28.5 grams
V1 = 45.5 ml
V2= 49.1 ml
The initial volume of water was 45.5 ml, when iron piece of 28.5 grams was added the final volume was 49.1 ml.
Putting the values in the equation of density
p = 
p = 7.91 g/ml
Since iron is a dense material it will occupy less volume
Answer:
713 nm. It is not visible with the naked eye.
Explanation:
Step 1: Given data
- Energy of light (E): 2.79 × 10⁻¹⁹ J
- Planck's constant (h): 6.63 × 10⁻³⁴ J.s
- Speed of light (c): 3.00 × 10⁸ m/s
Step 2: Calculate the wavelength of the light
We will use the Planck-Einstein equation.
E = h × c / λ
λ = h × c / E
λ = 6.63 × 10⁻³⁴ J.s × 3.00 × 10⁸ m/s / 2.79 × 10⁻¹⁹ J
λ = 7.13 × 10⁻⁷ m
Step 3: Convert "λ" to nm
We will use the relationship 1 m = 10⁹ nm.
7.13 × 10⁻⁷ m × (10⁹ nm/1 m) = 713 nm
This light is not in the 400-700 nm interval so it is not visible with the naked eye.
The volume did not change, it remained at 20 ml
<h3>Further explanation</h3>
Given
20 ml a sample gas at STP(273 K, 1 atm)
T₂=546 K
P₂=2 atm
Required
The volume
Solution
Combined gas Law :

Input the value :

The volume does not change because the pressure and temperature are increased by the same ratio as the initial conditions (to 2x)