How many atoms are present in a sample of Calcium (Ca) weighing 127.38g?

Answers

Answer 1

Answer:

1.9139 × 10²⁴ atoms Ca

General Formulas and Concepts:

Chemistry - Atomic Structure

Reading a Periodic TableUsing Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

Explanation:

Step 1: Define

127.38 g Ca

Step 2: Identify Conversions

Avogadro's Number

Molar Mass of Ca - 40.08 g/mol

Step 3: Convert

[tex]127.38 \ g \ Ca(\frac{1 \ mol \ Ca}{40.08 \ g \ Ca} )(\frac{6.022 \cdot 10^{23} atoms \ Ca}{1 \ mol \ Ca} )[/tex] = 1.91388 × 10²⁴ atoms Ca

Step 4: Check

We are given 5 sig figs. Follow sig fig rules and round.

1.91388 × 10²⁴ atoms Ca ≈ 1.9139 × 10²⁴ atoms Ca


Related Questions

how many electrons are there in 2 g of H2

Answers

Answer:

6.02 x 10²³ electrons

Explanation:

Given parameters:

Mass of H₂  = 2g

Unknown:

Number of electrons = ?

Solution:

To find the number of electrons, we must determine the number of moles of H₂ first.

 Number of moles  = [tex]\frac{mass}{molar mass}[/tex]  

  Molar mass of H₂   = 2(1)  = 2g/mol

Number of moles  = [tex]\frac{2}{2}[/tex]   = 1mol  

1 mole of a substance contains 6.02 x 10²³ particles

the particles can be protons, neutrons, electrons

So,

  2g of H₂ will contain 6.02 x 10²³ electrons.

Which of these is an example of chemical separation of a substance?
-Distillation
-Magnetism
-Paper Chromatography
-Bond breaking

Answers

Answer:

Bond broking

Explanation:

Bond broking.

A 6g sample of carbon allowed to burn in 20g of oxygen gas produce carbon dioxide. After the reaction, the mass of unreacted oxygen is 4 g. What mass of carbon dioxide was produced? show with steps

Answers

Answer:

Approximately [tex]22\;\rm g[/tex].

Explanation:

Look up the relative atomic mass data of carbon and oxygen on a modern periodic table:

[tex]\rm C[/tex]: [tex]12.011[/tex].[tex]\rm O[/tex]: [tex]15.999[/tex].

Calculate the formula mass of [tex]\rm O_2[/tex] and [tex]\rm CO_2[/tex]:

[tex]M(\rm O_2) = 2 \times 15.999 = 31.998\; \rm g \cdot mol^{-1}[/tex].

[tex]M(\rm CO_2) = 12.011 + 2 \times 15.999 = 44.009 \; \rm g \cdot mol^{-1}[/tex].

The question suggests that [tex]20\; \rm g - 4\; \rm g = 16\; \rm g[/tex] of [tex]\rm O_2[/tex] took part in this reaction. Calculate the number of moles of molecules in that [tex]16\; \rm g[/tex] of [tex]\rm O_2\,[/tex]:

[tex]\displaystyle n(\mathrm{O_2}) = \frac{m(\mathrm{O_2})}{M(\mathrm{O_2})} = \frac{16\; \rm g}{31.998\; \rm g \cdot mol^{-1}} \approx 0.500\; \rm mol[/tex].

Since [tex]\rm O_2[/tex] is in excess, it would react with [tex]\rm C[/tex] at a one-to-one ratio to produce [tex]\rm CO_2[/tex]:

[tex]\rm C + O_2 \to CO_2[/tex].

Notice the ratio between the coefficient of [tex]\rm O_2\![/tex] and [tex]\rm CO_2[/tex]: [tex]\displaystyle\frac{n(\mathrm{CO_2})}{n(\mathrm{O_2})} = \frac{1}{1}[/tex]. For each mole of [tex]\rm O_2[/tex] that is consumed, one mole of [tex]\rm CO_2\![/tex] will be produced.

The question implies that [tex]16\; \rm g[/tex], which is approximately [tex]0.500\; \rm mol[/tex], of [tex]\rm O_2[/tex] was consumed in this reaction. Accordingly, [tex]0.500\; \rm mol\![/tex] of [tex]\rm CO_2[/tex] will be produced.

Calculate the mass of that [tex]0.500\; \rm mol\![/tex] of [tex]\rm CO_2[/tex]:

[tex]m(\mathrm{CO_2}) = n(\mathrm{CO_2})\cdot M(\mathrm{CO_2}) \approx 22\; \rm g[/tex].

What element is represented in this model if the atomic number is 3?
This is science

Answers

Answer:

Lithium (Li)

Explanation:

Lithium has an atomic number of  3

Which of the following can be represented by a single chemical symbol?
Group of answer choices

potassium chloride

sulfate ion

water

sodium

Answers

Answer:

Sodium

Explanation:

Sodium is a pure chemical, hence it can be represented by the single chemical symbol Na.

Water has a chemical symbol of H2O, consisting of two, and not one, symbols, H and O.

Sulfate ion consists of a sulfide ion and four oxygen ions (SO4)2-. Hence, it does not fit.

Finally, potassium chloride has a chemical symbol of KCl. Consisting of two different chemical symbols, (K and Cl), it does not fit either.

Hope this helped!

property of an acide ​

Answers

Answer:

hi

Explanation:

acids are corrosive, rective when combined with bases form salt and when combined with metal form h2o

Answer:

page no,165 ma xa. yo question KO ans

How many atoms are present in a sample of Potassium (K) weighing 33.49g?

Answers

Answer:

5.158 × 10²³ atoms K

General Formulas and Concepts:

Chemistry - Atomic Structure

Reading a Periodic TableUsing Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

Explanation:

Step 1: Define

33.49 g K

Step 2: Identify Conversions

Avogadro's Number

Molar Mass of K - 39.10 g/mol

Step 3: Convert

[tex]33.49 \ g \ K(\frac{1 \ mol \ K}{39.10 \ g \ K} )(\frac{6.022 \cdot 10^{23} \ atoms \ K}{1 \ mol \ K} )[/tex] = 5.15797 × 10²³ atoms K

Step 4: Check

We are given 4 sig figs. Follow sig figs and round.

5.15797 × 10²³ atoms K ≈ 5.158 × 10²³ atoms K

One isotope of oxygen differs from another isotope of oxygen in *

Answers

Each isotope of Oxygen has a different number of neutrons

Further explanation

The elements in nature have several types of isotopes

Atomic mass is the average atomic mass of all its isotopes

Isotopes are atoms has the same number of protons but has a different number of neutrons.

So Isotopes are elements that have the same Atomic Number (Proton)

Some of the isotopes of oxygen are:

[tex]\tt _8^{16}O,_8^{17}O,_8^{18}O[/tex]

Each isotope has 8 protons and 8 electrons but has a different number of neutrons

For O-16: number of neutrons = 16-8 = 8

For O-17: number of neutrons = 17-8 = 9

For O-18: number of neutrons = 18-8 = 10

HELP!!!
i will mark brainliest ​

Answers

Answer:

Blank #1: noble gas

Blank #2: bonding

Blank #3: octet rule

Blank #4: share

Blank #5: filled

Blank #6: halogen

Please give me brianliest!!

help me solve. this is science. Which one is it

Answers

Answer:

d is the correct answer i think

What do the rows of the periodic table indicate?

Answers

Answer:

The rows on the periodic table are called periods. All the elements in a period have valence electrons in the same shell. The number of valence electrons increases from left to right in the period. When the shell is full, a new row is started and the process repeats.

Explanation:

hope this helps..

Three friends were kicking soccer balls at a neighborhood field. Three soccer balls were rolling across the field. The black soccer ball has less mass than the blue and orange balls, which have equal mass. All three soccer balls were kicked by one of the friends, but not all from the same direction. Use the information in the diagram to answer.


Which soccer ball(s) experienced the strongest force? How do you know?

A. All three soccer balls experienced the same force because they changed speed by the same amount.

B the orange soccer ball it has more mass and the fastest ending speed

c. the blue soccer ball it takes a stronger force to slow down a more massive object than to speed it up.

D the blue and orange soccer balls they have more mass than the black soccer ball changed speed by the same amount

Answers

Answer: d :The blue and orange soccer balls; they have more mass than the black soccer ball, but changed speed by the same amount.

Answer:

the answer is d

Explanation:

what is hydrophobic

Answers

Answer:

water fearing particle can be termed as HYDROPHOBIC

Answer:

Hydrophobic means "scared of water" or "the fear of water."

Hydro = water

phobic = fear

You'll use this at one point in Biology class.

Which of the following is true about waves?
A.
They are always visible.
B.
They always move matter.
C.
They carry energy.
D.
They can only travel though outer space.

Answers

Answer:

c. they carry energy is the answer

Answer:

C. they carry energy

Explanation:

Energy can be carried from one place to another by waves, including water, light, and sound waves. Waves are oscillating disturbances that travel through but do not move matter.

Infrared radiation escaping from hot coals is an example of invisible waves carrying energy. This energy can be felt as heat.

Can someone help me plz for BRAINLIST I swear I’ll give it to you !! I’m in 6th grade ( just started ) please help I’m begging !!

Answers

Answer:

Lithium                    Li                        3                 3                 4

Titanium                Ti                        22               22               26

Cobalt                   Co                      27                27               32

Silicon                    Si                       14                 14                14

Platinum                 Pt                      78                 78               117

Bromine                 Br                      35                 35               45

Nickel                     Ni                     28                  28               31

Manganese            Mn                   25                    25             30

Boron                      B                       5                     5                6

Oxygen                   O                       8                     8                8

Zinc                         Zn                      30                  30             35

Lead                        Pb                      82                   82            125

Explanation:

Can I have brainliest? This took me like an hour to find the answers and type the answers. TYSMMMMMMMMMMMMMMM  

Edit: I am also in 6th grade, but I looked it up because I haven't learned this yet.

You are doing math homework and get frustrated and throw the 7 kg book with a force of 47
Newtons. How much acceleration will the book have when you throw it?

Answers

Answer:

The answer is 6.71 m/s²

Explanation:

The acceleration of an object given it's mass and the force acting on it can be found by using the formula

[tex]a = \frac{f}{m} \\ [/tex]

f is the force

m is the mass

From the question we have

[tex]a = \frac{47}{7} \\ = 6.714285...[/tex]

We have the final answer as

6.71 m/s²

Hope this helps you

2. How can glass be a liquid if it's so hard?

Answers

Explanation:

Glass is not a liquid in the strictest sense of the word. But it is also not a standard solid. The chemistry of glass is complex and research is ongoing, but the current consensus is that glass is a phase of matter all its own, known as an "amorphous solid". Scientists refer to any amorphous solid as a "glass". Glass transitions are highly complex and cannot be treated in the same way as traditional phase transitions.

Answer:

It's a liquid state before its cooled.

3.) All matter has both physical and chemical properties. A physical property is one that does not change the chemical nature of matter. Which of these choices is a physical property?
A.) height
B.) flammability
C.) ability to rust
D.) reaction with water

Answers

Answer:

D

Explanation:

It would be D because you are observing the reaction and don’t change anything

Am I correct?? Help please

Answers

Answer:

I would say you are correct.

Explanation:

Answer:

I believe it'll be A (even though you chose it already).

Explanation:

Which of the following does not apply to water molecules?

Water molecules are polar
Water has cohesive properties
Water is less dense as a solid than a liquid
Water is not a very good solvent

Answers

Answer:

It is the last one.

Explanation:

Water molecules are polar, they have cohesive properties, and water is less dense when it is solid than when it is a liquid, that is why ice floats in liquid water. However, water is a very good solvent, it can dissolve many solids, including sugar, salt, and other hydrophilic substances.

Please help! It would be amazing if you can!!

Answers

Answer:

3) Warm Temperatures and High pressures

Explanation:

This is the typical characteristic of southern air masses moving north

(02.01 LC)
Which landform represents a large area of thick ice that moves slowly?

Answers

Answer:

Glacier

Explanation:

A glacier because glaciers contain thick layers of ice.

what is the empirical formula of a compound that has a carbon to hydrogen ratio 2-6

Answers

CH3 is the empirical formula of a compound that has a carbon to hydrogen ratio 2-6.

What is empirical formula?

The empirical formula of a chemical compound is the simplest and most basic ratio of the constituent elements present in it. It is written as the smallest whole-number ratio of the constituent elements, and does not indicate the amount or concentration of each element.

The empirical formula of a compound is the simplest whole number ratio of atoms in a molecule. In this case, the given carbon to hydrogen ratio of the compound is 2:6, which can be simplified to 1:3. This means that for every one carbon atom, there are three hydrogen atoms in the compound.

6H / 2C × 1/2 / 1/2 → 3 H / 1C

Therefore, the empirical formula of this compound is CH3.

To learn more about empirical formula the link

https://brainly.com/question/14044066

#SPJ1

Please help!!!! This equation is balanced: CaCO3 - CaO + CO2
True
False

Answers

Answer: false

Step by step explanation

which groups have elements with more than one positive oxidation state?

Answers

Answer:

(Ar, Xe, Rn) is the answer

According to the electronic configuration groups three to twelve have elements with more than one positive oxidation state.

What is electronic configuration?

Electronic configuration is defined as the distribution of electrons which are present in an atom or molecule in atomic or molecular orbitals.It describes how each electron moves independently in an orbital.

Knowledge of electronic configuration is necessary for understanding the structure of periodic table.It helps in understanding the chemical properties of elements.

Elements undergo chemical reactions in order to achieve stability. Main group elements obey the octet rule in their electronic configuration while the transition elements follow the 18 electron rule. Noble elements have valence shell complete in ground state and hence are said to be stable.

Learn more about electronic configuration,here:

https://brainly.com/question/13497372

#SPJ6

When 2.5 moles of N2 react according to the reaction below, how many moles of NH3 will be produced?
N2 + 3 H2 --> 2 NH3
O 2.5 moles NH3
0 2.0 moles NH3
O 1.3 moles NH3
5.0 moles NH3

Answers

Answer:

5 mol

Explanation:

by stoichiometry

nN2/1=nNH3/2

2.5=nNH3/2

nNH3=2.5×2

nNH3= 5 mol

Answer: I got 5.0 moles

Explanation:

Procedure: Step by step- what procedures should be followed while making the colors of the different fireworks (the shells and launch mechanisms will be made by the physics and design classes) the colors are: silver, white, gold and pink plz i need help ​

Answers

Answer:

It chemistry babe

Explanation:

What does the text indicate about the relationship between distance and gravitational force?

Answers

Answer:

The force of gravity is inversely related to the distance the alien is from Earth; this means that force of gravity decreases as the distance between the alien and Earth increases. As the distance between the alien and the surface of the planet increases, the force of gravity decreases.

Explanation:

If all objects masses are the same, then the object with the least ___ is the densest?

Possible Answers:
A: Mass
B: Volume
C: Weight
D: Density

Answers

It’s either A or B, Sorry, I’m really not sure..

Answer:

its weight

Explanation:

mass is how much space it takes up the volume stays the same density is what happens after so its weight

What liquid is the most vicious ?
A) water
B) skim milk
C)salt water
D) pancake syrup

Answers

Viscosity is basically how thick a liquid is so pancake syrup would be the answer
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