Answer:
1. 57.5%
2. 27.89 g
Explanation:
1. Determination of the percentage of sodium in sodium hydroxide.
Molar mass of NaOH = 23 + 16 + 1 = 40 g/mol
Mass of Na in NaOH = 23 g
Percentage of Na = mass of Na / Molar mass of NaOH × 100
Percentage of Na = 23/40 × 100
Percentage of Na = 57.5%
2. Determination of the mass of sodium in 48.5 g of sodium hydroxide.
Molar mass of NaOH = 23 + 16 + 1 = 40 g/mol
Mass of Na in NaOH = 23 g
Total mass of NaOH = 48.5 g
Mass composition of Na = mass of Na / Molar mass of NaOH × Total mass
Mass composition of Na = 23/40 × 48.5
Mass composition of Na = 27.89 g
CH4 + 2O2 -> 2H2O + CO2
You need to add a 2 in front of the O2 and H2O in order to balance the equation.
Rutherford’s, Bohr’s, and the quantum models say that electrons behave as particles, electron is negatively charged and electrons behave both particles and wave respectively.
<h3>What Rutherford’s, Bohr’s, and the quantum models say about electron?</h3>
Bohr model states that electrons behave as particles, Rutherford's model proposed that the negatively charged electrons surround the nucleus of an atom whereas quantum model explains that the electron has both particle and wave behavior.
So we can conclude that Rutherford’s, Bohr’s, and the quantum models say that electrons behave as particles, electron is negatively charged and electrons behave both particles and wave respectively.
Learn more about electron here: brainly.com/question/860094
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The
amount of a substance can be converted into grams of that substance by using
the molar mass. It is a physical property of a substance which describes the
mass per mole of the substance. The molar mass of Zn is 65.38 g/ mol.
Multiplying the given amount of Zn with the molar mass will yield to the
mass of the substance.<span>
</span>
<span>1.0 x 10^-3</span><span> x 65.38 =</span><span> </span><span>0.0654 g Zn</span>
Because the atom is neutral, it has no charge. For this to happen, the number of positive and negative charges must be the same. Therefore, because there are 11 -1 charged electrons, there must also be 11 +1 charged protons
So the answer is (2)