Answer:
Element is made up of the atoms or isotopes. Isotopes are where only neutrons change in number, such as 3 turning to 2 or to 5. Atom is where it is not changed and it is the original, and example is instead of Carbon13 it is just Carbon. I hope this helps.
Answer: The statement (B) is not true about chemical reactions.
Explanation:
A chemical reaction rate is affected by the several factors few of which are temperature, concentration of reactants, surface area etc.
In a chemical reaction, if temperature is increased then the rate of reaction will increase because it will increase the average kinetic energy of the reactant molecules. Thus, large number of molecules will have minimum energy required for an effective collision.
It is known that increasing the amount of reactants will increase the rate of reaction.
Therefore, rate of reaction will change if concentration or temperature is changed.
Hence, the statement (B) is not true about chemical reactions.
Answer : The amount of oxygen gas collected are, 0.217 mol
Explanation :
Using ideal gas equation :
where,
P = pressure of gas = 
(1 atm = 760 torr)
V = volume of gas = 5 L
T = temperature of gas = 
n = number of moles of gas = ?
R = gas constant = 0.0821 L.atm/mol.K
Now put all the given values in the ideal gas equation, we get:
Thus, the amount of oxygen gas collected are, 0.217 mol
The pressure in atm exerted by 1 mole of methane placed into a bulb with a volume of 244.6 mL at 25°C is 101.94atm.
<h3>How to calculate pressure?</h3>
The pressure of an ideal gas can be calculated using the following formula:
PV = nRT
Where;
- P = pressure
- V = volume
- n = number of moles
- R = gas law constant
- T = temperature
According to information in this question;
- T = 25°C = 25 + 273 = 298K
- V = 244.6mL = 0.24L
- R = 0.0821 Latm/Kmol
P × 0.24 = 1 × 0.0821 × 298
0.24P = 24.47
P = 24.47/0.24
P = 101.94atm
Therefore, the pressure in atm exerted by 1 mole of methane placed into a bulb with a volume of 244.6 mL at 25°C is 101.94atm.
Learn more about pressure at: brainly.com/question/11464844
