Answer: 94.13 L
Explanation: In STP in an ideal gas there is a standard value for both temperature and pressure. At STP,pressure is equal to 1atm and the temperature at 0°C is equal to 273.15K. This problem is an ideal gas so we use PV=nRT where R is a constant R= 0.08205 L.atm/mol.K.
To find volume, derive the equation, it becomes V=nRT/P. Substitute the values. V= 4.20 mol( 0.08205L.atm/mol.K)(273.15K) / 1 atm = 94.13 L. The mole units, atm and K will be cancelled out and L will be the remaining unit which is for volume.
According to the law of conservation of mass, what is the same on both sides of a balanced chemical equation?
A. the volume of the substances
B. the subscripts
C. the total mass of atoms
D. the coefficients
Answer:
A balanced equation demonstrates the conservation of mass by having the same number of each type of atom on both sides of the arrow.
Explanation:
Every chemical equation adheres to the law of conservation of mass, which states that matter cannot be created or destroyed. ... Use coefficients of products and reactants to balance the number of atoms of an element on both sides of a chemical equation.
Consider the balanced equation for the combustion of methane.
CH
4
+
2O
2
→
CO
2
+
2H
2
O
All balanced chemical equations must have the same number of each type of atom on both sides of the arrow.
In this equation, we have 1
C
atom, 4
H
atoms, and 4
O
atoms on each side of the arrow.
The number of atoms does not change, so the total mass of all the atoms is the same before and after the reaction. Mass is conserved.
Here is a video that discusses the importance of balancing a chemical equation.
Answer:

Explanation:
1. Calculate the work
w = - pΔV = -4.3 atm × (43 L - 20 L) = -4.3 × 23 L·atm = -98.9 L·atm
2. Convert litre-atmospheres to joules

The negative sign indicates that the work was done against the surroundings.
When a substance dissociates into OH- ions, they are classified as bases.