How many molecules of sodium oxide will be created if 187 grams of oxygen reacts with excess sodium? 4na + o2 -> 2na2o a. 11.69 x 1023 molecules of na2o

7.04 × 10²⁴ molecules of Na₂O

Explanation:

1) Balanced chemical equation (given):

4 Na(s) + O₂ (g) → 2Na₂O (s)

2) Mole ratio:

1 mol O₂ : 2 mol Na₂O

3) Number of moles of O₂ in 187 grams of oxygen:

Molar mass O₂ = 32.00 g/molNumber of moles = mass in grams / molar mass = 187 g / 32.00 g/mol = 5.844 mol

4) Number of moles of Na₂O:

Proportion: 1 mol O₂ / 2 mol Na₂O = 5.844 mol O₂ / xx = 5.844 mol O₂ (2 mol Na₂O / 1 mol O₂) = 11.688 mol Na₂O

5) Number of molecules

Number of molecules = number of moles × Avogadro's numberNumber of molecules = 11.688 mol × 6.022 × 10²³ molecules/mol =

                                               = 7.04 × 10 ²⁴ molecules ← answer

The answer is rounded to three significant figures.

The independent variable is the type of music.the dependent variable is the pulse rate.the intervening variable is the age of the subject.if the mother does not like rock, her pulse is likely to not increase.the same might be true for the sister.the friend may like rap and gets excited.to establish cause/effect relationship, all of the subjects must be consistent.hope i .