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How is density found

Yanka [14]

Through mass and volume.

3 0

2 years ago

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What is the mass of 1.7 × 1023 atoms of zinc (Zn)?

Rudiy27

Number of moles is defined as the ratio of given mass in g to the molar mass.

The mathematical formula is:

Number of moles = $\frac{given mass in g}{molar mass}$ (1)

Number of zinc atoms is equal to $1.7\times10^{23}$ , by Avogadro number, number of moles can be calculated.

As, 1 mol= $6.022\times10^{23}$ atoms, hence,

$1.7\times10^{23}\times\frac{1 mol}{6.022\times10^{23} }$

= 0.2822 mol

Now, from formula (1), calculate mass in g (molar mass of zinc = 65.4 g/mol)

0.2822 mol = $\frac{mass in g}{65.4 g/mol}$

mass in g = ${0.2822 mol \times 65.4 g/mol$

= 18.45588 g

Thus, by rounding off the above number, it will come near about 19 g approximately.

Hence, option (C) is the correct answer.

8 0

3 years ago

Crime scene investigators keep a wide variety of compounds on hand to help with identifying unknown substances they find in the

almond37 [142]

The powder could be acetaminophen, analgesic having chemical formula $C_{17}H_{21}NO_{4}$

<h3>What is an empirical formula?</h3>

A chemical formula showing the simplest ratio of elements in a compound rather than the total number of atoms in the molecule.

We are given:

Percentage of C = 67.31 %

Percentage of H = 6.978 %

Percentage of N = 4.617 %

Percentage of O = 21.10 %

Let the mass of the compound be 100 g. So, the percentages given are taken as mass.

Mass of C = 67.31 g

Mass of H = 6.978 g

Mass of N = 4.617 g

Mass of O = 21.10 g

To formulate the empirical formula, we need to follow some steps:

Step 1: Converting the given masses into moles.

Moles of carbon = $\frac{mass}{molar \;mass}$

Moles of carbon = $\frac{67.31g}{12g/mole}$

=5.60 moles

Moles of hydrogen = $\frac{mass}{molar \;mass}$

Moles of hydrogen = $\frac{6.978 g}{1 g/mole}$

=6.978 moles

Moles of nitrogen = $\frac{mass}{molar \;mass}$

Moles of nitrogen = $\frac{4.617 g}{14 g/mole}$

=0.329 moles

Moles of oxygen = $\frac{mass}{molar \;mass}$

Moles of oxygen = $\frac{21.10 g}{16 g/mole}$

=1.31 moles

Step 2: Calculating the mole ratio of the given elements.

For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 0.329 moles.

We get the ratio of C : H : N : O = 17 : 21 : 1 : 4

The empirical formula for the given compound is $C_{17}H_{21}NO_{4}$ .

Learn more about the empirical formula here:

brainly.com/question/14044066

#SPJ1

3 0

1 year ago

Find the oxidizing agent and the reducing agent.

Vladimir [108]

Oxidizing agent is that which is reduced and the reducing agent is that which is oxidized. Reduced is when the charged is decreased and oxidized when the charge is increased.

(1) 2Na + 2H2O(l) --> 2NaOH(aq) + H2(g)
The charge of Na in the reactant is 0 and the charge of Na in the NaOH is +1. Na is oxidized. Hence, it is the reducing agent.

The charge of H in H2O is +1 while that in H2 is 0. H is reduced. Hence, it is the oxidizing agent.

(2) C(s) + O2(g) --> CO2(g)

The charge of C in the reactant side is 0 and that its charge in CO2 is +4. C is oxidized. Hence, it is the reducing agent.

The charge of O in O2 is 0 while in CO2, its charge is -2. O is reduced. Hence, it is the oxidizing agent.

(3) 2MnO⁻⁴ + SO2 + 2H2O --> 2Mn²⁺ + 5SO2⁻⁴ 4H⁺

The charge of Mn in MnO⁻⁴ is 4+ while its charge in Mn²⁺ is 2+. Mn is reduced. Hence, it is the oxidizing agent.

The charged of S in SO2 is -4 while its charge in SO₂⁻⁴ is 0. S is oxidized. Hence, it is the reducing agent.

8 0

2 years ago

Define Triple point of water?

Ilia_Sergeevich [38]

<h2>Hey There!</h2><h2>_____________________________________</h2><h2>Answer:</h2><h2>_____________________________________</h2><h2>TRIPLE POINT:</h2>

Triple point is that temperature, at which the substance is found in all three states i.e. solid, liquid and gas. Every substance has different triple point, because Triple point is just above the freezing point and each substance has different freezing and boiling point.

<h2>_____________________________________</h2><h2>WATER:</h2>

Water has a Melting point or Freezing Point (MP or FP) of $0^0$ C or 273K and Boiling point (BP) $100^{0}$ C or 373 K. Since the triple point is just above the MP or FP thus Triple Point of water is $0.01^{0}$ C or 273.16K.

<h2>_____________________________________</h2><h2>Best Regards,</h2><h2>'Borz'</h2><h2 />

6 0

2 years ago

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