1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
yan [13]
3 years ago
5

How many atoms are in 65.05g of Na?​

Chemistry
1 answer:
Artemon [7]3 years ago
7 0

Answer:

grsdg

Explanation:

sadga

You might be interested in
Even though we are well into the course Dumbledore notices some of the students are still having trouble with significant figure
Sphinxa [80]

Answer:

B) 2

Explanation:

Significant figures : The figures in a number which express the value -the magnitude of a quantity to a specific degree of accuracy is known as significant digits.

The rule apply for the multiplication and division is :

The least number of significant figures in any number of the problem determines the number of significant figures in the answer.

The rule apply for the addition and subtraction is :

The least precise number present after the decimal point determines the number of significant figures in the answer.

(3.478-2.31) = 1.168 ≅ 1.17 (Rounded to least decimal digit)

(4.428-3.56) = 0.868 ≅ 0.87 (Rounded to least decimal digit)

So,

1.17 * 0.87 = 1.0  (Rounded to least significant)

Answer - two significant digits

5 0
3 years ago
A mixture of carbon dioxide and helium gases is maintained in a 7.91 L flask at a pressure of 1.42 atm and a temperature of 33 °
Crank

Answer:

The gas mixture contains 1.038 grams of helium

Explanation:

<u>Step 1:</u> Data given

Volume of the flask = 7.91 L

Total Pressure = 1.42 atm

Temperature = 33 °C

Mass of CO2 = 8.25 grams

Molar mass of CO2 = 44.01 g/mol

Molar mass of He = 4 g/mol

<u>Step 2</u>: Calculate total number moles of gas

p*V = n*R*T

⇒ p = the pressure = 1.42 atm

⇒ V = the volume = 7.91 L

⇒ n= the number of moles = TO BE DETERMINED

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

⇒ T = the temperature = 33 °C = 306 Kelvin

n = (p*V)/(R*T)

n = (1.42*7.91)/(0.08206 * 306)

n = 0.447 moles

<u>Step 3</u>: Calculate moles of CO2

Moles CO2 = mass CO2 / Molar mass CO2

Moles CO2 = 8.25 grams / 44.01 g/mol

Moles CO2 = 0.1875 moles

<u>Step 4:</u> Calculate moles of Helium

Moles Helium = total moles of gas - moles of CO2

Moles Helium = 0.447 - 0.1875 = 0.2595 moles of helium

<u>Step 5: </u> Calculate mass of helium

Mass of helium = moles of helium * molar mass of helium

Mass of helium = 0.2595 moles * 4 g/mol

Mass of helium = 1.038 grams

The gas mixture contains 1.038 grams of helium

8 0
2 years ago
15.0 mL of an unknown clear liquid is added to a 50 mL graduated cylinder. The mass of the liquid is determined to be 12.7 grams
sveticcg [70]

Answer:

\boxed {\tt A. \ d=0.85 \ g/mL}

Explanation:

Density is found by dividing the mass by the volume.

d=\frac{m}{v}

The mass of the liquid is 12.7 grams.

We know that 15 mL of this liquid was added to a 50 mL graduated cylinder. Therefore, the volume is 15 mL. The 50 mL is not relevant, it only tells us about the graduated cylinder.

m= 12.7 \ g\\v= 15 \ mL

Substitute the values into the formula.

d=\frac{12.7 \ g}{ 15 mL}

Divide.

d=0.846666667 \ g/mL

Round to the nearest hundredth. The 6 in the tenth place tells us to round the 4 to a 5.

d \approx 0.85 \ g/mL

The density of the liquid is about 0.85 grams per milliliter and choice A is correct.

4 0
3 years ago
How many of grams of CuSO4 are in 475ml of a 2.0M aqueous solution
Anettt [7]

Answer:

151.63 g

Explanation:

We first get the number of moles;

Moles = Molarity × volume

          = 2.0 × 0.475

          = 0.95 moles

1 mole of CuSO4 = 159.609 g/mol

Therefore;

Mass = moles × molar mas

         = 0.95 moles × 159.609 g/mol

         = 151.63 g

8 0
3 years ago
Read 2 more answers
What’s the difference between a learned behavior in an inherited behavior? Give one example of each
AleksAgata [21]

Answer:

A learned behavior is a behavior that develops during an animal's lifetime. Tying one's shoes or solving a math problem are examples of learned behaviors. An inherited behavior is a behavior that an animal is born with. It does not have to be taught. For example, a bird can build a nest for the first time without any help.

Explanation:

3 0
3 years ago
Read 2 more answers
Other questions:
  • What is the molarity of a solution that contains 20 grams of salt dissolved in 3.0 L of solution? The molar mass of water is 18g
    8·2 answers
  • Determine whether each of the following is exothermic or endothermic and indicate the sign of ΔH.
    10·1 answer
  • Which phrases describe all the outer planets' motion? Check all that apply.
    14·1 answer
  • The density of lead is 11.3
    9·2 answers
  • BaCl2 (aq) + AgNO3 (aq) →
    8·2 answers
  • Pls help i beg
    14·1 answer
  • What is meant by the term activation energy?
    6·1 answer
  • Which TWO substances are reactants in the chemical reactions of cellular respiration
    5·2 answers
  • The chemical equation below shows the process of forming water. Balance the equation by calculating the coefficients. H2 + O2 H2
    9·1 answer
  • 1. Why is it a problem that most black-footed ferrets today are closely related?
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!