Answer:
THE NEW PRESSURE OF THE HELIUM GAS IS 124kPa AFTER THE VOLUME WAS INCREASED FROM 2.48 L TO 2.98 L
Explanation:
Using Boyle's law which states that at constant temperature, the pressure of a given gas is inversely proportional to the volume occupied by the gas.
Mathematically,
P1 V1 = P2 V2
P1 = 150 kPa = 150 * 10^3 Pa
V1 = 2.48 L
V2 = 2.98 L
P2 = ?
Rearranging the formula making P2 the subject of the equation, we obtain;
P2 = P1 V1 / V2
P2 = 150 * 10^3 * 2.48 / 2.98
P2 = 372 * 10 ^3 / 2.98
P2 = 124.83 * 10^3 Pa or 124.8kPa
In other words, the new pressure of the helium gas after its volume was increased from 2.48 L to 2.98 L is 124.8kPa.
Answer:
Measure its mass
Measure its volume
Measure its number of moles
Explanation:
I could not break unless you hit it with a sledge hammer
Answer: 72 grams of 
are needed to completely burn 19.7 g 
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to molecular mass and contains avogadro's number 
of particles.
To calculate the number of moles, we use the equation:
Putting in the values we get:
According to stoichiometry:
1 mole of 
requires 5 moles of oxygen
0.45 moles of require= 
moles of oxygen
Mass of 
72 grams of are needed to completely burn 19.7 g
Electrons: negative
Protons: positive
Neutrons: nuetral
