A MOLECULE
A molecule is a true representative of a covalent bond.
The balanced chemical reaction is:
<span>2Na + 2H2O → 2NaOH + H2
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We first use the amount of hydrogen gas to be produced and the molar mass of the hydrogen gas to determine the amount in moles to be produced. Then, we use the relation from the reaction to relate H2 to Na.
53.2 g H2 ( 1 mol / 2.02 g ) ( 2 mol Na / 1 mol H2 ) ( 22.99 g / 1 mol ) = 1210.96 g Na
1210.96 g Na ( 1 mL / 0.97 g ) = 1248.41 mL Na needed</span>
The quantum mechanical model is used to describe the energy and most likely location of an electron.
Answer: Option A
<u>Explanation:
</u>
The quantum mechanical model leads to the introduction of quantum numbers representing the energy levels, sub-shells, orbitals as well as spin states of the electrons. So according to the quantum numbers we can perfectly define the position and energy of any electron in an element.
According to Pauli’s principle, any two electron cannot be having same set of quantum numbers. So, using the principle quantum number, azimuthal quantum number, magnetic and spin quantum number, we can define the energy and location of an electron in the atom.
There are 5.01 × 10-⁷grams in 4.07 x 10¹⁵molecules of calcium hydroxide.
HOW TO CALCULATE MASS:
The mass of a substance can be calculated by multiplying the number of moles in the substance by its molecular mass.
However, given that the number of molecules in calcium hydroxide is 4.07 x 10¹⁵molecules, we need to calculate the number of moles in Ca(OH)2 as follows:
no. of moles of Ca(OH)2 = 4.07 x 10¹⁵ ÷ 6.02 × 10²³
no. of moles = 0.676 × 10-⁸
no. of moles = 6.76 × 10-⁹ moles.
Molar mass of Ca(OH)2 = 74.093 g/mol
Mass of Ca(OH)2 = 74.093 × 6.76 × 10-⁹ moles
Mass = 5.01 × 10-⁷grams.
Therefore, there are 5.01 × 10-⁷grams in 4.07 x 10¹⁵molecules of calcium hydroxide.
Learn more about how to calculate mass at: brainly.com/question/8101390?referrer=searchResults
Answer:
d. 54.9 kPa
Explanation:
mmHg and Pa are units of pressure used in chemistry principally in the study of gases. 1mmHg is equal to 133.322Pa. 412mmHg are:
412 mmHg * (133.322Pa / 1mmHg) = 54929 Pa
The prefix K (Kilo) represents one thousand of the determined unit.
54929Pa are:
54929Pa * (1KPa / 1000Pa) = 54.9kPa
Right answer is:
<h3>d. 54.9 kPa
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