<span>There are 34 hydrogen atoms.
</span>
Answer:
Molality = 0.43 m
Explanation:
Given data:
Mass of barium sulfide = 25.4 g
Mass of water = 349 g (349 g/1000 = 0.349 Kg)
Molality of water = ?
Solution:
Number of moles of barium sulfide:
Number of moles = mass/molar mass
Number of moles = 25.4 g/169.39 g/mol
Number of moles = 0.15 mol
Molality:
Molality = number of moles o f solute/ Kg of solvent
Molality = 0.15 mol / 0.349 Kg
Molality = 0.43 m
Combustion<span> Reactions, a </span>combustion<span> reaction always has oxygen as one reactant. The second reactant is always a hydrocarbon, which is a compound made up of carbon and hydrogen. A</span>combustion<span> reaction also always produces such as C02 and H20</span>
Answer:
4.90% is approximately the new Dextrose concentration.
Explanation:
Volume by Volume percent is given by ;
Volume percentage of dextrose solution = 5%
In 100 mL of solution 5 ml of dextrose is present.
Now, volume sterile water added was equal to the 40% of volume of dextrose volume.
So, volume of the sterile water added = 
Total volume of the solution after addition of water = 100 mL + 1 mL = 102 mL
New concentration of dextrose will be;
4.90% is approximately the new Dextrose concentration.
The element has :
- core electrons : 10
- valence electron : 5
<h3>Further explanation </h3>
Valence electrons : electrons used in forming bonds (the outer shell)
Core electrons : electrons that belong to atoms except for valence electrons. It is located close to the core and fills the inner shell.
Electron configurations for an element with the atomic number: 15 1s²2s²2p⁶3s²3p³
Neutral atoms ⇒ atomic number= number of protons=number of electrons
The electron configuration shows that the valence electron of the element = 5(3s²3p³) so the number of Core electrons:
Core electron = atomic number (total number of electrons) - valence electron
Core electron = 15 - 15
Core electron = 10
