All categories

2 years ago

Which is an example of making a quantitative observation?

Chemistry

1 answer:

lions [1.4K]2 years ago

8 0

Measuring the surface of an oil painting and finding its dimensions 12 to be 12 inches

You might be interested in

What volume of O2 collected at 22.0 and 728 mmHg would be produce by the decomposition of 8.15 g KClO3?

adell [148]

Answer:

There is 2.52 L of O2 collected

Explanation:

Step 1: Data given:

Temperature = 22.0 °C

Pressure = 728 mmHg = 728 /760 = 0.958 atm

Mass of KClO3 = 8.15 grams

Molar mass of KClO3 = 122.55 g/mol

Step 2: The balanced equation

2KClO3(s) → 2KCl(s) + 3O2(g)

Step 3: Calculate moles of KClO3

Moles KClO3 = mass KClO3 / molar mass KClO3

Moles KClO3= 8.15 grams / 122.55 g/mol

Moles KClO3 = 0.0665 moles

Step 4: Calculate moles of O2

For 2 moles of KClO3 we'll have 2 moles of KCl and 3 moles of O2 produced

For 0.0665 moles of KClO3 we have 3/2 * 0.0665 = 0.09975 moles

Step 5: Calculate vlume of O2

p*V = n*R*T

V = (n*R*T)/p

⇒ with n = the number of moles O2 = 0.09975 moles

⇒ with R = the gas constant = 0.08206 L*atm/K*mol

⇒ with T = 22.0 °C = 273 +22 = 295 Kelvin

⇒ with p = 0.958 atm

V = (0.09975 * 0.08206 * 295) / 0.958

V = 2.52 L

There is 2.52 L of O2 collected

7 0

2 years ago

What is the density if<br> a sample of rock has a mass of 69<br> g and a volume of<br> 23<br> ml?

kiruha [24]

Density = mass / volume

= 69g / 23 ml

= 3 g / ml.

Thus, the density of the sample is 3 grams per ml or 3g/ ml

4 0

3 years ago

Read 2 more answers

How many moles are in 1.51x10^26 atoms of xenon (Xe)? Please and thank you :)!!

RoseWind [281]

<h3>Answer:</h3>

251 mol Xe

<h3>General Formulas and Concepts:</h3>

<u>Math</u>

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

<u>Chemistry</u>

<u>Atomic Structure</u>

Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

<u>Stoichiometry</u>

Using Dimensional Analysis

<h3>Explanation:</h3>

<u>Step 1: Define</u>

[Given] 1.51 × 10²⁶ atoms Xe

[Solve] moles Xe

<u>Step 2: Identify Conversions</u>

Avogadro's Number

<u>Step 3: Convert</u>

[DA] Set up: $\displaystyle 1.51 \cdot 10^{26} \ atoms \ Xe(\frac{1 \ mol \ Xe}{6.022 \cdot 10^{23} \ atoms \ Xe})$
[DA] Multiply/Divide [Cancel out units]: $\displaystyle 250.747 \ mol \ Xe$

<u>Step 4: Check</u>

<em>Follow sig fig rule and round. We are given 3 sig figs.</em>

250.747 mol Xe ≈ 251 mol Xe

3 0

2 years ago

In the formula for carbon tetrahydride, CH4, the percent composition of all elements is:

creativ13 [48]

C%=12/16*100=3/4*100=75%
H%=25%

8 0

2 years ago

Read 2 more answers

NASA communicates with the Space Shuttle and International Space Station using Ku-band microwave radio. Suppose NASA transmits a

Margarita [4]

Answer:

λ = 0.0167 m = 16.7 mm

Explanation:

The wavelength of these radio waves can be found out by using the formula for the speed of radio waves:

v = fλ

where,

v = speed of radio waves = speed of light = 3 x 10⁸ m/s

f = frequency of radio waves = 18 GHz = 18 x 10⁹ Hz

λ = Wavelength = ?

Therefore,

3 x 10⁸ m/s = (18 x 10⁹ Hz)λ

λ = (3 x 10⁸ m/s)/(18 x 10⁹ Hz)

4 0

2 years ago