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:80KM is distance. 30KM north is displacement.
Explanation:
Answer:
8.72 × 10^5 moles
Explanation:
To find the number of moles in 5.25 x 10^29 molecules of sucrose, we divide the number of molecules by Avagadro constant (6.02 × 10²³ molecules). That is;
no. of moles = no. of molecules ÷ 6.02 × 10²³ molecules
In this case of sucrose, no of moles contained is as follows;
5.25 × 10^29 ÷ 6.02 × 10²³
5.25/6.02 × 10^ (29-23)
0.872 × 10^6
= 8.72 × 10^5 moles
Answer : The standard enthalpy of formation of ethylene is, 51.8 kJ/mole
Explanation :
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The formation reaction of 
will be,
The intermediate balanced chemical reaction will be,
(1) 
(2) 
(3) 
Now we will reverse the reaction 1, multiply reaction 2 and 3 by 2 then adding all the equations, we get :
(1) 
(2) 
(3) 
The expression for enthalpy of formation of will be,
Therefore, the standard enthalpy of formation of ethylene is, 51.8 kJ/mole
The best and most correct answer among the choices provided by the question is the second choice or letter B which is hand washing. Hand washing is the most natural way of preventing the risk of food-borne disease without<span> affecting the taste or nutrient content of foods such as lettuce and other vegetables.</span>
