INFORMATION:
We must find the number of valence electrons for magnesium
STEP BY STEP EXPLANATION:
In order to know the number of valence electrons for Mg, we need to locate the element in the periodic table
Since Mg is in the second group of the periodic table, it has two valence electrons.
ANSWER:
B) 2
I don’t know about 1 But number 2 is AB + xH2O = AB.xH2O
Stars born larger than 8 solar masses usually retain enough mass to undergo core collapse, with the resulting shock wave producing a Type Ib supernova (spectra without Hydrogen or Silicon lines, with Helium lines), a Type Ic supernova (without Hydrogen or Helium or Silicon lines) or a Type II supernova
I hope it’s what you need
Answer:
Mass = 76.176 g
Explanation:
Given data:
Mass of lead(II) chloride produced = 62.9 g
Mass of lead(II) nitrate used = ?
Solution:
Chemical equation:
Pb(NO₃)₂ + 2HCl → PbCl₂ + 2HNO₃
Number of moles of lead(II) chloride:
Number of moles = mass/molar mass
Number of moles = 62.9 g/ 278.1 g/mol
Number of moles = 0.23 mol
Now we will compare the moles of lead(II) chloride with Pb(NO₃)₂ from balance chemical equation:
PbCl₂ : Pb(NO₃)₂
1 : 1
0.23 : 0.23
Mass of Pb(NO₃)₂:
Mass = number of moles × molar mass
Mass = 0.23 mol × 331.2 g/mol
Mass = 76.176 g
Answer:
1.76 g is the mass of Ne is in the container.
Explanation:
We use the equation given by ideal gas which follows:
where,
P = pressure of the gas = 650 mm Hg
V = Volume of the gas = 2.50 L
T = Temperature of the gas = ![25^oC=[25+273]K=298K](https://tex.z-dn.net/?f=25%5EoC%3D%5B25%2B273%5DK%3D298K)
R = Gas constant = 
n = number of moles of Ne gas = ?
Putting values in above equation, we get:
Also, molar mass of Ne = 20.1797 g/mol
So, 
<u>1.76 g is the mass of Ne is in the container.</u>
