Answer:
Only 2moles are produced from it
If the half-life of a radioactive substances is 590 million years and you have 40 atoms of it, how many half-lives will have passed when 5 atoms remain
Answer:
3
Explanation:
Applying,
[tex]2^{n'}[/tex] = R/R'............... Equation 1
Where n' = number of halflives that have passed, R = Original atom of the substance, R' = atom of the substance left after decay.
From the question,
Given: R = 40 atoms, R' = 5 atoms
Substitute these values into equation 1
[tex]2^{n'}[/tex] = 40/5
[tex]2^{n'}[/tex] = 8
[tex]2^{n'}[/tex] = 2³
Equation the base,
n' = 3
Which of the following techniques can be applied to separate the components of a mixture?
Answer:
fractional distillation
filtering
evaporation
help me with chemistry pls. i have no idea anything related to this subject :')
Question 24:
Answer C : Q is placed in group 13 and period 2.
Question 25:
Answer C : II and IV.
Question 26:
Answer D
Is FeS iron (ll) sulfide or iron (lll) sulfide?
Answer:
the valence of S is -2. For FeS to be neutral the valence of Fe used must be +2
and since Iron (II) has its valency 2, FeS will be Iron (II) Sulfide.
how much energy is required to melt 2kg of aluminium
Please help!!
Chemical reactions and Nuclear reactions cause matter to change in different ways. Witch TWO statements decribe how matter changes only in nuclear reactions.
• A. The automic nuclei change.
• B. Some energy is transformed into mass.
• C. The total mass of the reactions is conserved.
• D. New elements are formed
Answer:
Answer is 2nd
Explanation:
some energy is transformed into mass
Anyone please help I’m in summer school please
Answer:
1. Absolute time, also known as Newtonian time is a time that exists independent of the observer of the time, and therefore, can only be expressed through mathematics
Absolute dating is a dating method that makes use of the radioactive property of matter and is determined through dating of radioactive isotopes present
Absolute time (dating) is found through radioactive dating
2. Radioactive isotopes are atoms that have the property of unstable proton neutron combination or excess energy nucleus. They can be fined as unstable element
3. A stabilized isotope are the decay product atoms of the element which are non radioactive.
4. The half life is the time it takes the original isotope to decay into the decay product
5. To determine the age of a rock, the proportion of the original isotope to the amount of decay product in the rock is compared
6. The isotope used to date organic materials is carbon-14
7. The isotope used to date rocks with comparable age to the Earth is Uranium-238 that has a half life of 4.468 billion years
8. The half life of carbon-14 is only 5,700 years while the age of a dinosaur is between 245 and 66 million years ago, and therefore, carbon is absent in most fossils
9. Uranium-238 is only found in igneous or volcanic rocks and not in metamorphic rocks, therefore, fossils of dinosaur as well as other fossils that are buried in sedimentary materials, including sand and clay, cannot be determined by Uranium-238
Explanation:
How many grams of hydrogen is produced from 12.5 G of MG reacting with hydrochloric acid in this balanced equation?
Mg+ 2HCL —>MgCl2+H2
Answer:
1.03 grams of hydrogen is produced from 12.5 g of Mg reacting with hydrochloric acid.
Explanation:
The balanced reaction is:
Mg+ 2 HCl → MgCl₂ + H₂
By stoichiometry of the reaction, the following amounts of moles of each compound participate in the reaction:
Mg: 1 moleHCl: 2 molesMgCl₂: 1 moleH₂: 1 moleBeing the molar mass of each compound:
Mg: 24.31 g/moleHCl: 36.45 g/moleMgCl₂: 95.21 g/moleH₂: 2 g/moleBy reaction stoichiometry, the following mass amounts of each compound participate in the reaction:
Mg: 1 mole* 24.31 g/mole= 24.31 gHCl: 2 moles* 36.45 g/mole= 72.9 gMgCl₂: 1 mole* 95.21 g/mole= 95.21 gH₂: 1 mole* 2 g/mole= 2 gThen you can apply the following rule of three: if by stoichiometry 24.31 grams of Mg produces 2 grams of H₂, 12.5 grams of Mg produces how much mass of H₂?
[tex]mass of H_{2} =\frac{12.5 grams of Mg* 2 grams of H_{2}}{24.31 grams of Mg}[/tex]
mass of H₂= 1.03 grams
1.03 grams of hydrogen is produced from 12.5 g of Mg reacting with hydrochloric acid.
Calculate the molar mass AND identify the gas if 3.25 kg of this gas is stored in a 15.00 L tank and exerts a pressure of 120.0 atm at a constant temperature of 66.0°C.
Answer:
is your question correct
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or not
On the set of a movie, dry ice (solid carbon dioxide) is used to make the appearance of fog. After the dry ice is taken out of cold storage, it is placed on the ground. As dry ice warms, it converts from a solid directly to a gas. Gaseous carbon dioxide has a density greater than air, thus allowing it to move across the ground as if it were fog. Which statement best describes this process
Answer:
- The dry ice is cooling the ground it rests upon as heat is transferred from the ground to the dry ice.
Explanation:
The above statement correctly elaborates the process of using dry ice to develop the appearance of fog. When the dry ice is placed on the ground, the heat of the ground is transferred to the dry ice. This will result in the increase in the kinetic energy of the CO2 molecules. Thus, the solid will directly convert into gas and it will lead to the formation of gas in the air. Since CO2 possesses a higher density, it will look like fog and thus, giving the perfect shot for the fog scene.
A 26.04 g mixture of zinc and sodium is reacted with a stoichiometric amount of sulfuric acid. The reaction mixture is then reacted with 199 mL of 2.51 M barium chloride to produce the maximum possible amount of barium sulfate. Determine the percent sodium by mass in the original mixture.
Answer:
[tex]\%Na=88.2\%[/tex]
Explanation:
Hello there!
In this case, according to the given equation, it turns out possible to say that the reaction with barium chloride proceeds with sodium sulfate only, which means we can calculate the mass of sodium in the sample by using the following procedure:
[tex]H_2SO_4+2Na\rightarrow H_2+Na_2SO_4\\\\Na_2SO_4+BaCl_2\rightarrow 2NaCl+BaSO_4[/tex]
Whereas the mass of zinc is calculated as follows:
[tex]m_{Na}=0.199L*2.51\frac{molBaCl_2}{L}*\frac{1molNa_2SO_4}{1molBaCl_2}*\frac{2molNa}{1molNa_2SO_4} *\frac{23.0gNa}{1molZn}\\\\m_{Na}=23.0g[/tex]
Thus, the percent sodium by mass would be:
[tex]\%Na=\frac{23.0}{26.04g}*100\% \\\\\%Na=88.2\%[/tex]
Regards!
Calculate gram-formula mass of AlCl3, show your work.
Answer:
133.48gfm
Explanation:
element number Mass
Al 1 26.98(1)
Cl 3 35.5(3)
then add the above values
= 133.48gfm
Plz Help I have One more time To retake and I can't fail it..
Answer:
D. is the answer which is copper is a conductor because it's valency can move from atom to atom.
Calculate the mass of potassium acid phthalate (HKC8H4O4) that will require about 15 mL of the approximately 0.1 M NaOH solution. Measure approximately this mass on a tared piece of weighing paper and transfer it to a clean, labeled Erlenmeyer flask. Similarly, prepare all three samples, recording the masses for each. Dissolve the KHP in about 50 mL of R.O. water and add 2 drops of phenolphthalein.
Answer:
0.31 g
Explanation:
The equation of the reaction;
HKC8H4O4(aq) + NaOH(aq) ----> Na(KC8H4O4)(aq) + H2O(l)
Number of moles of NaOH = 15/1000 L × 0.1 M
= 0.0015 moles
Since the reaction is 1:1, 0.0015 moles of KHP reacted;
Number of moles of KHP = mass of KHP reacted/molar mass of KHP
Mass of KHP = Number of moles of KHP × molar mass of KHP
Mass of KHP = 0.0015 moles × 204.22 g/mol
Mass of KHP = 0.31 g
PLS HELP I WILL REWARD MOST BRAINLIEST
You are in a lab and you use 57.50 g of Na(s) to react with Cl(g). Below is the reaction that happens from this.
Na + Cl2 → NaCl
Your percent yield is 95%. From this info what is the actual yield?
Answer:
Actual yield = 138.94 g
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
2Na + Cl₂ —> 2NaCl
Next, we shall determine the mass of Na that reacted and the mass of NaCl produced from the balanced equation. This can be obtained as follow:
Molar mass of Na = 23 g/mol
Mass of Na from the balanced equation = 2 × 23 = 46 g
Molar mass of NaCl = 23 + 35.5
= 58.5 g/mol
Mass of NaCl from the balanced equation = 2 × 58.5 = 117 g
SUMMARY:
From the balanced equation above,
46 gof Na reacted to produce 117 g of NaCl.
Next, we shall determine the theoretical yield NaCl. This can be obtained as follow:
From the balanced equation above,
46 gof Na reacted to produce 117 g of NaCl.
Therefore, 57.50 g of Na will react to produce = (57.50 × 117)/46 = 146.25 g of NaCl.
Thus, the theoretical yield of NaCl is 146.25 g
Finally, we shall determine the actual yield of NaCl. This can be obtained as follow:
Percentage yield = 95%
Theoretical yield = 146.25 g
Actual yield =?
Percentage yield = Actual yield / Theoretical yield × 100
95% = Actual yield / 146.25
Cross multiply
Actual yield = 95% × 146.25
Actual yield = 95/100 × 146.25
Actual yield = 0.95 × 146.25
Actual yield = 138.94 g
copper II carbonate in a crucible produced only 7g of copper II oxide. What was the percentage yield of copper II oxide
The question is incomplete, the complete question is;
.On heating 12.4 g of copper (II) carbonate in a crucible only 7.0g of copper (II) oxide was produced. What was the % yield of copper (II) oxide ? [Cu=64,C=12,O=16]
Answer:
87.5%
Explanation:
CuCO3 -------> CuO + CO2
Number of moles of CuCO3 = 12.4g/123.55 g/mol = 0.1 moles
Since the reaction is 1:1,
Mass of CuO produced = 0.1 moles × 80g/mol = 8 g
Hence,
% yield = actual yield/theoretical yield × 100
% yield = 7/8 × 100
% yield = 87.5%
draw the structure of iso -pentylpropanoate
option with explaination
Answer:
B. it's water of crystallization.
the water of crystallization, that is the number of molecules of water attached to One Copper atom gives blue color to the hydrated salt (CuSO4.5H2O)
Which of the following best describes an atomic number? An element's identity is defined by its atomic number; this means it represents the number of
options: A) protons plus neutrons in its nucleus.
B) electrons in the element.
C) protons in its nucleus.
D) neutrons in its nucleus.
The number of protons in a nucleus is called the atomic number and ever equals the number of electrons in orbit about that nucleus.
How do you find the atomic number?The atomic number of an atom is equal to the number of protons in the nucleus of an atom or the number of electrons in an electrically neutral atom.
Suppose in a oxygen atom, there are 8 electrons and 8 protons. Thus the atomic number of O atom = number of electrons = number of protons = 8.
Thus, option "C" is correct, protons in its nucleus.
To learn more about atomic number click here:
https://brainly.com/question/16858932
Question 1: Alkanes, Alkenes, and Alkynes
Complete the table by labeling each molecule an alkane, alkene, or alkyne.
Answer: The labelling of each molecule is listed below:
B.) alkyne
C.) Alkane
D.) alkyne
I.) alkene
Explanation:
In organic chemistry, if an organic compound contains atoms joined only by single covalent bonds, the compound is said to be saturated. The ALKANES are said to be saturated hydrocarbons. For example butane and hexane that is shown in option F and G respectively. If an organic compound contains carbon atoms joined by double or triple covalent bonds, the compound is said to be unsaturated. For example Octene and butyne as seen in option E and H respectively.
Furthermore, hydrocarbons possess8g a set of carbon-carbon double covalent bonds,>C=C<, in their carbon chains form the homologous series called ALKENES while those possessing a set of carbon-carbon triple covalent bond in their carbon chains form the ALKYNE series
From the questions above, a more informative formula known as the structural formula is used to represent the various organic substances. The formula indicates how the atoms are arranged within the molecule of a substance. A structural formula is usually shown as a planar for convenience and does not imply a flat molecule. It shows the actual arrangement of the atoms in space and the angles between the bonds. Therefore options C, D and I are alkane,alkyne and alkene respectively.
the covalent bond with the greatest polarity would form in which of the atom pairs below?
A. Br - Br
B. S - O
C. C - P
D. C - O
E. B - O
The covalent bond with the greatest polarity would form in this atom pair: B. S-O.
Ionic character refers to a percentage of difference between the electronegativity (polarity) of two (2) atoms that are bonded covalently.
Hence, ionic character is directly proportional to the difference between the electronegativity (polarity) of two (2) atoms that forms a covalent bond.
Furthermore, bonded atoms of chemical element that are having the greatest difference in electronegativity usually forms covalent bonds with the greatest polarity.
The electronegativity of some of the chemical element are:
Sulfur (S) = 2.58Oxygen (0) = 3.5Bromine (Br) = 2.96Carbon (Ca) = 2.55Boron (B) = 2.04Phosphorus (P) = 2.19By observation, the difference between the electronegativity (polarity) of Sulfur (S) and Oxygen (0) would form a covalent bond with the greatest polarity.
[tex]S-O=3.5-2.58=0.92[/tex]
Read more: https://brainly.com/question/18214726
the valency of sodium is one give reason
Answer:
here
Explanation:
The valency of sodium is 1 because it loses it's one valence electron to gain its octet state (state of having 8 electrons in shell) during the chemical reaction.
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An electrolytic cell transferred 0.10 m o l of electrons when a constant current of 2.0 A was applied. How many hours did this take?
Answer:
1.34 hr
Explanation:
From the question given above, the following data were obtained:
Number of mole of electron (e) = 0.1 mole
Current (I) = 2 A
Time (t) =?
Next, we shall determine the quantity of electricity transferred. This can be obtained as follow:
1 mole of electron = 96500 C
Therefore,
0.1 mole of electron = 0.1 × 96500
0.1 mole of electron = 9650 C
Thus, 9650 C of electricity was transferred.
Next, we shall determine the time. This can be obtained as follow:
Current (I) = 2 A
Quantity of electricity (Q) = 9650 C
Time (t) =?
Q = It
9650 = 2 × t
Divide both side by 2
t = 9650 / 2
t = 4825 s
Finally, we shall convert 4825 s to hour. This can be obtained as follow:
3600 s = 1 hr
Therefore,
4825 s = 4825 s× 1 hr / 3600 s
4825 s = 1.34 hr
Thus, the time taken is 1.34 hr
What is pH value in simple words?
Explain the charge, the location and the size of protons, and electron.
Protons are positively charged particles that are located inside the nucleus at the center of the atom. Protons have a mass of 1 amu or atomic mass unit.
Electrons are negatively charged particles found outside the nucleus. Electrons have a mass of approximately 0 amu or atomic mass unit.
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question
question
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What volume (in L) will a 32 g sample of butane gas, C4H10(9), occupy at a temperature of 45.0 °C and a pressure of 728
mm Hg?
Answer:
The volume of the gas is 0.015 m^3.
Explanation:
mass, m = 32 g
Temperature, T = 45 °C = 45 + 273 = 318 K
Pressure, P = 728 mm of hg = 0.728 x 13.6 x 1000 x 9.8 = 97027.84 Pa
Atomic mass = 4 x 12 + 10 x 1 = 58 g
Use the ideal gas equation
Let the volume is V.
P V = n R T
[tex]97027.8 \times V = \frac{32}{58}\times 8.31 \times 318 \\\\V = 0.015 m^3[/tex]
Explanation:
The volume of the gas occupied can be calculated by using the ideal gas equation:
[tex]PV=nRT[/tex]
where,
P=pressure of the gas in atm
V=volume of the gas in L.
n=number of moles of the gas
R=0.0821L.atm.mol-1.K-1
T=absolute temperature
To get the volume of the gas, follow the below steps:
1) Calculate the number of moles of gas:
Number of moles of butane=mass of butane given/its molecular mass
[tex]=32g/58.0g/mol\\=0.55mol[/tex]
2) Convert temperature into kelvin scale:
T=(45+273)K=318K
3)Convert pressure into atm:
760 mm Hg =1 atm
then,
728 mm Hg=
728 mm Hg x 1 atm /760 mm Hg
=0.957 atm
Substitute all these values in the ideal gas equation to get the volume:
[tex]V=\frac{nRT}{P} \\V=0.55mol x 0.0821 L.atm.mol-1.K-1 x 318K / 0.957 atm\\V=15.0L[/tex]
Answer:
The volume of butane gas is 15.0 L
¿Qué relación tienen los microorganismos patógenos con el cov1d
19 ?
Answer:
Lumayan poin gratis...
gw gatau lu pake bahasa apaan njink
An organic compound has the empirical formula C2H4O. what is the compound?
a. butanoic acid
b. butanol
c. ethanoic acid
d. ethanol
Answer:
The correct answer is - butanoic acid
Explanation:
An empirical formula is the general formula or base formula that is the simplest positive integer ratio of atoms present in a compound. The empirical formula is specific to specific compounds or types of compounds.
Among the given options, the empirical formula C2H4O is butanoic acid as the molecular formula of butanoic acid is - C4H8O2 which is multiple of C2H4O. Other compounds have different than this empirical formula.
What does this chemical energy reaction describe? Water-hydrogen+oxygen
Answer:
may be you mean water= hydrogen + oxygen, this reaction describes that water is made by the combination of hydrogen and oxygen.
name and describe four different types of chemical reactions and explain how you can predict which type might occur
Answer:
1. Combination (Synthesis) reaction
A + B → AB
2. Decomposition reaction
AB → A + B
3. Displacement reaction
A + BC → AB + C
4. Double displacement reaction
AB + CD → AD + BC
5. Combustion reaction
[tex]CH_{4} + 20_{2} → CO_{2} 2Hx_{2} O[/tex]
A combination reaction, also known as a synthesis reaction, is a reaction in which two or more substances combine to form a single new substance. Combination reactions can also be called synthesis reactions.
A decomposition reaction is a reaction in which a compound breaks down into two or more simpler substances.
A single-replacement reaction is a reaction in which one element replaces a similar element in a compound.
A double-replacement reaction is a reaction in which the positive and negative ions of two ionic compounds exchange places to form two new compounds.
A combustion reaction is a reaction in which a substance reacts with oxygen gas, releasing energy in the form of light and heat. Combustion reactions must involve O2 as one reactant. The combustion of hydrogen gas produces water vapor
Explanation: Hope this helps and good luck :))
