Answer:
14.8 × 10²³ molecules
Explanation:
Given data:
Mass of sulfuric acid = 240 g
Number of molecules = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
Number of moles of sulfuric acid
<em>Number of moles = mass/ molar mass</em>
Number of moles = 240 g/ 98 g/mol
Number of moles = 2.45 mol
Number of molecules:
1 mole = 6.022 × 10²³ molecules
2.45 × 6.022 × 10²³ molecules
14.8 × 10²³ molecules
A substance that is impenetrable by x-rays is described as being radiopaque.
Radiopaque substances will not allow x-rays and or other forms of radiations to pass through them.
Instead, they absorb or block the rays and when used in radiology, they appear white or light gray on photographic films.
Radiopaque materials are applied in generating ultrasound images and other forms of clinical procedures.
More on radiopaque materials can be found here: brainly.com/question/10583205?referrer=searchResults
Answer:
T =76.13 K
Explanation:
Given data:
Temperature of gas = ?
Volume of gas = 250 mL(250/1000 = 0.25 L)
Mass of helium = 0.40 g
Pressure of gas = 253.25 kpa (253.25/101 = 2.5 atm)
Solution:
Formula:
PV = nRT
First of all we will determine the number of moles of helium.
Number of moles = mass/ molar mass
Number of moles = 0.40 g/ 4 g/mol
Number of moles = 0.1 mol
Now we will put the values.
R = general gas constant = 0.0821 atm.L/ mol.K
T = PV/nR
T =2.5 atm× 0.25 L /0.1 mol ×0.0821 atm.L/ mol.K
T = 0.625 /0.00821/K
T =76.13 K
