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3 years ago

What time did frosty die in frosty meets his demise

Chemistry

1 answer:

sergejj [24]3 years ago

8 0

Answer:

this lesson is the third in a three-part series about the nucleus, isotopes, and radioactive decay. The first lesson, Isotopes of Pennies, deals with isotopes and atomic mass. The second lesson, Radioactive Decay: A Sweet Simulation of Half-life, introduces the idea of half-life.

By the end of the 8th grade, students should know that all matter is made up of atoms, which are far too small to see directly through a microscope. They should also understand that the atoms of any element are alike but are different from atoms of other elements. Atoms may stick together in well-defined molecules or they could be packed together in large arrays.

For students, understanding the general architecture of the atom and the roles played by the main constituents of the atom in determining the properties of materials now becomes relevant. Having learned earlier that all the atoms of an element are identical and are different from those of all other elements, students now come up against the idea that, on the contrary, atoms of the same element can differ in important ways. (Benchmarks for Science Literacy, p. 79.)

In this lesson, students will be asked to consider the case of when Frosty the Snowman met his demise (began to melt). The exercise they will go through of working backwards from measurements to age should help them understand how scientists use carbon dating to try to determine the age of fossils and other materials. To be able to do this lesson and understand the idea of half-life, students should understand ratios and the multiplication of fractions, and be somewhat comfortable with probability

Explanation:

You might be interested in

Freon, a very useful refrigerant, is produced in the following reaction:

Svetach [21]

Answer:

The chemistry will need 2*10⁶ moles of antimony trifluoride.

Explanation:

The balanced reaction is:

3 CCl₄ (g) + 2 SbF₃ (s) → 3 CCl₂F₂(g) + 2 SbCl₃ (s)

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of each compound participate in the reaction:

CCl₄: 3 moles
SbF₃: 2 moles
CCl₂F₂: 3 moles
SbCl₃: 2 moles

You can apply the following rule of three: if by reaction stoichiometry 3 moles of freon are produced by 2 moles of antimony trifluoride, 3*10⁶ moles of Freon are produced from how many moles of antimony trifluoride?

$moles of antimony trifluoride=\frac{3*10^{6} moles of freon*2 moles of antimony trifluoride}{3 moles of freon}$

moles of antimony trifluoride= 2*10⁶

The chemistry will need 2*10⁶ moles of antimony trifluoride.

8 0

3 years ago

How many atoms are in 73.9g of potassium oxide

denis-greek [22]

Answer: $4.69(10)^{23} atoms$

Explanation:

Firstly, we have to find the Molecular mass of potassium oxide ( $K_{2}0$ ):

$K$ atomic mass: 39 u

$O$ atomic mass: 16 u

$K_{2}O$ molecular mass: $39(2) g/mol+16g/mol=94 g/mol$

This means that in 1 mole of $K_{2}O$ there are $94 g$ and we need to find how many moles there are in $73.9 g$ $K_{2}O$ :

1 mole of $K_{2}O$ ----- $94 g$ of $K_{2}O$

$X$ ----- $73.9 g$ of $K_{2}O$

$X=\frac{(73.9 g)(1 mole)}{94 g}$

$X=0.78 mole$ This is the quantity of moles in 73.9 g of potassium oxide

Now we can calculate the number of atoms in 73.9 g of potassium oxide by the following relation:

$N_{atoms}=(X)(N_{A})$

Where:

$N_{atoms}$ is the number of atoms in 73.9g of potassium oxide

$N_{A}=6.0221(10)^{23}/mol$ is the Avogadro's number, which is determined by the number of particles (or atoms) in a mole.

Then:

$N_{atoms}=(0.78 mole)(6.0221(10)^{23}/mol)$

$N_{atoms}=4.69(10)^{23} atoms$ This is the quantity of atoms in 73.9g of potassium oxide

6 0

4 years ago

Why does temperature increase with altitude through the stratosphere? The stratosphere is closest to the sun. The ozone layer is

lukranit [14]

Temperature increase with altitude through the stratosphere because "The ozone layer is found in the stratosphere".

Stratosphere is the second layer of the atmosphere of the Earth. 20% of the mass of the atmosphere is found in this layer.
The temperature of the stratosphere increases as the altitude increases due to the presence of the ozone layer in it as the ozone layer absorbs the ultraviolet radiations of the Sun which causes an increase in the temperature of this layer.

8 0

3 years ago

Read 2 more answers

What are the physical properties of oxygen

torisob [31]

The physical properties are Boiling Point, Melting Point, Psat, Liquid Density, Molecular Weight, Critical Temp, and Critical Pressure

7 0

4 years ago

Please help need ideas for lab report

dem82 [27]

Answer:

Objectives(s):

In your own words, what is the purpose of this lab?

To teach me about chemical compounds

Hypothesis:

In this section, please include the if/then statements you developed during your lab activity. These statements reflect your predicted outcomes for the experiment. If you combine two certain compounds, then it will make a new compound.

Procedure:

The materials and procedures are listed in your virtual lab. You do not need to repeat them here. However, you should note if you experienced any errors or other factors that might affect your outcome. Using your summary questions at the end of your virtual lab activity, please clearly define the dependent and independent variables of the experiment.

Data:

Record the composition of each of your compounds below. Be sure to include the number of atoms for each element. An example has been supplied for you.

Compound Name

Chemical Formula

Sodium (Na)

Atoms

Calcium (Ca)

Atoms

Hydrogen (H)

Atoms

Oxygen (O)

Atoms

Carbon (C)

Atoms

Chlorine (Cl)

Atoms

Ex: Sodium

hypochlorite

NaClO

Carbon Tetrachloride

CCl4

Water

H2O

Calcium Hydroxide and Hydrogen Gas

Ca(OH)2 + H2

Sodium Hydride

NaH

Sodium Hydroxide

NaOH

Chlorine Dioxide

ClO2

Hydrogen Chloride

HCl

Table Salt

NaCl

Bleach

NaClO

Conclusion:

Your conclusion will include a summary of the lab results and an interpretation of the results. Please answer all questions in complete sentences using your own words.

Using two to three sentences, summarize what you investigated and observed in this lab. I investigated how chemical compounds work and what to use to put them together.

Why do you believe knowing how elements and compounds react together is essential in everyday matters? So, you can cook and stop injuries, these two things happen a lot in day-to-day life.

Some elements are more "reactive" than other elements; why do you think this is? Because certain elements in the compound may react more to fire or water and many other elements.

Choose one of the compounds from the table and explain how you know the numbers of atoms in your formula. Because if you add all the atoms, put in that’s the total amount. For example, water has one hydrogen atom and one oxygen atom, so water has two atoms.

Is it possible for two different compounds to be made from the exact same two elements? Why or why not? With a limited number of elements (less than 120 are known), does this mean we also have a small number of compounds, or do we have many compounds in this world? Yes, it is possible like water and hydrogen peroxide. The formula of water is H20 but hydrogen peroxide has one more oxygen-H202.

Explanation:

7 0

3 years ago