What are you making a hypothesis for
The answer to this question is B
Hello,
A physical change describes a change that does physically and does not display “chemical” signs which are signs that indicate a precipitate being formed, change in color, density, or producing gas, etc. “Tearing a piece of paper in half” is a physical change because like I said earlier it doesn’t show any chemical change signs. I hope this helps you out!
Answer:
1.07 g Ba
Explanation:
Hello there!
In this case, according to the definition of the Avogadro's number and the molar mass, it is possible to say that 6.022x10^{23} atoms of barium equal one mole, and at the same time, 1 mole equals 137.327 grams of this element; thus, it is possible to say that 6.022x10^{23} atoms of barium have a mass of 137.327 grams; therefore, it i possible for us to calculate the required mass in grams as shown below:

Best regards!
Answer:
0.052mL
Explanation:
1mole of a gas occupy 22.4L.
Therefore, 1 mole of CO2 will also occupy 22.4L.
If 1mole of CO2 occupies 22.4L,
Then 2.3moles of CO2 will occupy = 2.3 x 22.4 = 51.52L
coverting this volume to mL, we simply divide by 1000 as shown below:
51.52/1000 = 0.05152mL = 0.052mL