Based on the ideal gas relation:
PV = nRT
where P = pressure ; V = volume ; T = temperature
n = number of moles; R = gas constant = 0.0821 L atm/mol-K
Step 1: Find the number of moles of O2
n = PV/RT = 1 * 3.90/0.0821*273 = 0.1740 moles
Step 2: Calculate the molecules of O2
Now, 1 mole of O2 corresponds to 6.023 * 10²³ molecules of O2
Therefore, 0.1740 moles of O2 corresponds to-
0.1740 moles of O2 * 6.023*10²³ molecules of O2/1 mole of O2
= 1.048 * 10²³ molecules of O2
Answer: 6.38 moles of
are needed to react with 2.55 mol of 
Explanation:
The balanced chemical reaction for the combustion of ethyne is:

According to stoichiometry:
2 moles of
require = 5 moles of 
Thus 2.55 mol of
require =
moles of 
Thus 6.38 moles of
are needed to react with 2.55 mol of 
Answer:
The number of protons also determines the identity of the element. ... Since the atom is electrically neutral, the number of electrons must equal the number of protons.
It became thicker and its viscosity decreased and cannot flow as easily as before.
You ignite a chemical reaction by adding the borax solution to the glue mixture.
In a chemical reaction, the molecules of glue and borax combine to form a flexible, springy new substance. With rubber's vulcanization serving as a model, chemical cross-linking has been extensively employed to change the physical properties of polymeric materials.
Chemical links between polymer chains provide a substance with a more solid structure and perhaps a better-defined shape. It thickened and lost viscosity, making it more difficult to flow than it once could.
Learn more about the chemical reaction here brainly.com/question/16714866
#SPJ4.
Answer:
4Fe + 3O2 + 6H2O → 4Fe(OH)3
Explanation:
The chemical formula for rust is Fe2O3 and is commonly known as ferric oxide or iron oxide. The final product is a series of chemical reactions simplified below as- The rusting of the iron formula is simply 4Fe + 3O2 + 6H2O → 4Fe(OH)3. The rusting process requires both the elements of oxygen and water.