<h3>
Answer:</h3>
250.756 moles He
<h3>
Explanation:</h3>
From the question we are given;
Volume, L = 685 L
Temperature, T = 621 K
Pressure, P = 189 × 10 kPa
We are required to calculate the number of moles of the gas,
Using the Ideal gas equation,
PV = nRT, where P is the pressure, V is the volume, T is the temperature, n is the number of moles, and R is the ideal gas constant.
We can replace the known variables and constant in the equation to get the unknown variable, n.
Using ideal gas constant as 8.3145 L.kPa/K/mol



n = 250.756 moles
The moles of helium contained in the sphere is 250.756 moles
Answer:
1 billion molecules O₂
Explanation:
From my research, a human red blood cell contains approximately 270 million hemoglobin molecules.
A hemoglobin molecule contains four heme groups, <em>each of which has an iron ion forming a coordination complex that carries every dioxygen molecule. </em>Therefore for each hemoglobin molecule, we will have 4 dioxygen molecules. The heme groups are responsible for the transport of every dioxygen and other diatomic gases.
Hence, the number of O₂ molecules in a red blood cell saturated with 100% will be:

So, the correct answer is 1 billion of O₂ molecules.
Have a nice day!
Answer:
The correct answer would be metamorphosis.
Metamorphosis is a biological process by which an immature form transforms into an adult form passing through numerous distinct stages.
It is mainly observed in amphibians and insects. For example, frog and butterfly.
The life cycle of a butterfly can be summarized as shown below.
Steel is an alloy and consists of more than one element (mainly iron and carbon), therefore steel is a mixture.
Answer:
C
Explanation:
A gas is a state of matter that has no fixed shape and no fixed volume gases have lower density than other states of matter such as solids and liquids.