All the elements in one group have the same number of valence electrons.
The correct answer is <span>D) centrifuge the mixture because the substance with the highter density will be pulled to the bottom
When things spin around, like a centrifuge, the centripetal force draws things towards the middle. If you make it a bit like a spiral and put it sideways, then the denser thing will go to the bottom while the less dense ones will remain on the outside. </span>
Answer: 234.4K
Explanation:
Given that,
Original volume of gas (V1) = 5.00 L
Original temperature of gas (T1) = 20.0°C
[Convert 20.0°C to Kelvin by adding 273
20.0°C + 273 = 293K]
New volume of gas (V2) = 4.0L
New temperature of gas (T2) = ?
Since volume and temperature are given while pressure is held constant, apply the formula for Charle's law
V1/T1 = V2/T2
5.00L/293K = 4.0L/T2
To get the value of T2, cross multiply
5.00L x T2 = 293K x 4.0L
5.00L•T2 = 1172L•K
Divide both sides by 5.00L
5.00L•T2/5.00L = 1172L•K/5.00L
T2 = 234.4K
Thus, the new temperature of the gas is 234.4 Kelvin
Answer:
I believe 1+
Explanation:
when Na loses 1 electron in the outer shell it has 8 valence protons on it's new most outer shell. so now it has 11 protons and 10 electrons. that extra proton (positively charged) adds one extra charge. so +1
12 times breathe give 240 ml of pure 
. Each breathe gives 20 ml of .
Let us consider, volume of air per breathe= x ml.
Pure from inhaled air= 
ml and Pure from exhaled air= 
ml.
Pure from inhaled and exhaled air= 20 ml
So, + = 20
Therefore, x = 55.5 ml
So, volume of air per breath= 55.5 ml.
