Answer:
A = 65.46 u
Explanation:
Given that,
The composition of zinc is as follows :
Zn-64 = 48.63%
Zn-66 = 27.90%
Zn-67 = 4.10%
Zn-68 = 18.75%
Zn-70 = .62%
We need to find the average atomic mass of the given element. It can be solved as follows :
[tex]A=\dfrac{48.63\times 64+27.90\times 66+4.1\times 67+18.75\times 68+0.62\times 70}{100}\\A=65.46\ u[/tex]
So, the average atomic mass of zinc is 65.46 u.
What is the valency of Aluminium and nitrate in Al(NO3)3 ?
Answer:xl/ck xLKsx
Explanation:sl/cs c/ls
Which drawing is structural model of C3H8?
Answer:
option B is the correct answer
El simbolo del ion que contiene 24 protones, 28 neutrones y 21 electrones es : A)Sc+3 B)Sc-3 C)Sc D)Cr E)Cr-3
Answer:
Cr ^ 3 +
Explanation:
Recordemos que el número atómico es el número de protones en el núcleo del átomo. También corresponde al número de electrones en el átomo neutro.
Dado que el número de protones es 24, entonces el elemento debe ser cromo.
Si hay 21 electrones presentes, entonces se deben haber perdido 3 electrones para dar Cr ^ 3 +.
What is the salt produced in the stomach when calcium carbonate reacts with and neutralizes excess hydrochloric acid?
The salt CaCl2 (calcium chloride) and water (H2O) are formed in this reaction. Also formed is the gas carbon dioxide (CO2) which may cause a bloated feeling in the stomach. The acid that is secreted in your stomach is approximately 0.1 M (moles per liter) hydrochloric acid.
I hope it helps ●~●
Determine the excluded volume per mole and the volume actually occupied by a mole for a gas consisting of molecules with radius 167 pm. [Note: To obtain the volume in liters, we must express the radius in decimeters (dm).] Enter your answers in scientific notation.
Answer:
Explanation:
Volume of one mole of a gas = 22.4 litre.
No of molecules in one mole of gas = 6.02 x 10²³ .
Volume of one molecule = 4/3 π R³
= 4/3 x 3.14 x ( 167 x 10⁻¹² m )³
= 19.5 x 10⁶ x 10⁻³⁶ m³
=19.5 x 10⁻³⁰ m³
= 19.5 x 10⁻³⁰ x 10³ litre .
= 19.5 x 10⁻²⁷ litre .
So volume occupied by molecules in one mole of gas
= 19.5 x 10⁻²⁷ x 6.02 x 10²³ litre
117.4 x 10⁻⁴ litre
= .01174 litre.
Excluded volume
= ( 22.4 - .01174 ) litre .
= 22.388 litre.
To make a sarurated solution, 36 g of sodium chloride is dissolved in 100 g of water at 293 k . Find its concentration at this temperature
Answer:
The answer is "[tex]26.47\%[/tex]"
Explanation:
Sodium chloride solute mass[tex]=36 \ g[/tex]
Solvent water mass[tex]=100\ g[/tex]
Calculating the solution mass = Solute mass + solvent mass
[tex]= 36\ g +100\ g\\\\ = 136\ g\\\\[/tex]
Calculating the percentage of concentration:
[tex]= \frac{solute\ mass}{solvent\ mass} \times 100\\\\=\frac{36\ grm}{136\ grm} \times 100\\\\=0.2647 \times 100\\\\=26.47 \%[/tex]
What is the symbol for an ion with a 3+ charge, 28 electrons, and a mass number of 71
Answer:
Ga3+ is a gallium cation
Which of the following units is not an official SI unit?
a) kilogram
b) ampere
c) mole
d) liter
Answer:
liter
Explanation:
I think liter because it is not listed as a SI unit
Answer:
[tex]{ \bf{d). \: { \tt{litre}}}}[/tex]
How many bonds can a carbon atom form?
O A. 1
B. 2
C. 4
O D. 3
What is one way to neutralize acidic lakes using an acid-base reaction?
[tex]\huge\fcolorbox{red}{pink}{Answer ♥}[/tex]
Solutions for Neutralization of Acidic Lakes. ... A common solution to increase water hardness in acid lakes is to add lime, a high-alkalinity calcium compound to the acid lakes. This method is only temporary and very expensive, as it often needs to be applied every year.
Hope it helps uh ✌️✌️
Balance the equation of. _C + _O2 -- _CO
Explanation:
2C +O2 = 2CO
this will be the answer
Which statements are consistent with Dalton"s atomic theory as it was originally stated? Why? a. Sulfur and oxygen atoms have the same mass. b. All cobalt atoms are identical. c. Potassium and chlorine atoms combine in a 1:1 ratio to form potass...
The question is incomplete, the complete question is:
Which statements are consistent with Dalton's atomic theory as it was originally stated? Why?
a. Sulfur and oxygen atoms have the same mass.
b. All cobalt atoms are identical.
c. Potassium and chlorine atoms combine in a 1:1 ratio to form potassium chloride.
d. Lead atoms can be converted into gold.
Answer: The correct options are b) and c).
Explanation:
Some of the postulates of Dalton's atomic theory are:
All matter is made of very tiny particles called atoms that participate in chemical reactionsAtoms are indivisible particles that cannot be created or destroyed in a chemical reactionAtoms of a given element are identical in mass and chemical propertiesAtoms of different elements have different masses and chemical properties.Atoms combine in the ratio of small whole numbers to form compounds.The relative number and kinds of atoms are constant in a given compound.For the given options:
For a:
The statement is inconsistent with the theory as no two elements can have the same mass. Only atoms of the same element can have the same mass.
For b:This is consistent with the theory as atoms of the same element are identical.
For c:This is consistent with the theory as atoms combine in a simple whole number ratio.
For d:The statement is inconsistent with the theory as atoms of one element cannot be changed to atoms of other element.
Hence, the correct options are b) and c).
How many moles of sodium carbonate in 18.06x10 to the power 22
Answer:
[tex] moles = \frac{ number \: of \: particles}{6.02 \times {10}^{23} } [/tex]
=1.806×10^22/6.02×10^23
=0.03 moles
hope this helps :)
What is a rechargeable battery?
a group of electrochemical cells that can be recharged
a group of electrolytic cells that can be recharged
a group of electrochemical cells that do not need recharging
O a group of electrolytic cells that do not need recharging
WILL GIVE BRAINLIEST
Answer:
a group of electrochemical cells that can be recharged
hey armies.. how are you doing
Answer:
Nice and you
Explanation:
Please Mark me brainliest
True or false The atomic number of an element is always more than the mass number of that element.
The enthalpy of a reaction is -394 kJ/mol. How would you describe the
reaction?
A. Spontaneous
B. Exothermic
C. Endothermic
D. Nonspontaneous
Answer:
the reaction is spontaneous
Balance equation for. _Mg + _H3(PO4) --_Mg3(PO4)2+ _H2
cual es el tamaño de partícula del alcohol
Answer:
Las botellas de alcohol vienen en una variedad de tamaños. El estándar es de 750 ml, que también se conoce como "un quinto" porque es 1/5 de galón. Otros tamaños comunes de botellas de alcohol son 50ml, 100ml, 200ml, 375ml, 1L y 1.75L.
Explanation:
Which general equation shows a double-displacement reaction?
O A. AB + CD + AC + BD
O B. AB → A+B
O C. AB + CD → AD + CB
O D. A+B → AB
Answer:
O A. AB + CD + AC + BD
explanation:
Explanation:
A.ab+cd+ac+bd is your answer
A 10.0 L balloon contains helium gas at a pressure of 655 mmHg. What is the final pressure, in millimeters of mercury, if the final volume is 13.8 L? Please show your work in order to receive credit.
Answer:
474. 64 mm Hg
Explanation:
P1 = 655 mm Hg V1 = 10 LP2 = ? V2 = 13. 8 Lusing Boyle's Law that is
P1. V1 = P2. V2
655 × 10 = P2 × 13. 8
[tex]P2 = \frac{655 \times 10}{13.8} [/tex]
P2 = 474. 64 mm Hg
Which refers to substances that are complex molecules and contain carbon atoms bonded to hydrogen atoms?
o
O organic
O inorganic
ionic
metallic
Answer:
organic
Explanation:
Organic substances are those which contains covalently linked carbon to hydrogen (C-H) bonds in their structure. In other words, organic compounds or substances are uniquely composed of carbon and hydrogen atoms covalently linked together.
These substances usually contain a long chain of these bonds, hence, making them complex. Therefore, according to this question, substanves that are complex molecules and contain carbon atoms bonded to hydrogen atoms are referred to as ORGANIC SUBSTANCES.
Answer:
A. Organic
Explanation:
Q2.
This question is about metals and metal compounds.
(a)
Copper oxide reacts with hydrochloric acid to produce copper chloride and water.
Copper oxide is insoluble in water.
Copper oxide is gradually added to hydrochloric acid until in excess.
Magnesium reacts with hydrochloric acid to produce magnesium chloride and hydrogen.
Plan an investigation to find the accurate volume of hydrogen produced from
magnesium
You do not need to write about safety precautions.
Answer:
sry I don't know the answer
A sodium atom has 11 protons and 12 neutrons. What is the mass number of this sodium atom?
Sodium has a mass number of 23amu. Since sodium has 11 protons, the number of neutrons must be 23 – 11 = 12 neutrons.
Calculate the average atomic mass element X
Answer:
39.02 amu
Explanation:
The average atomic mass of an element can be calculated as follows :
[tex]X=\dfrac{9.67\times 38+78.68\times 39+11.34\times 40+0.31\times 41}{100}\\\\X=\dfrac{3902.29}{100}\\\\X=39.02\ amu[/tex]
So, the atomic mass of the element X is 39.02 amu.
List twelve types of industry
Answer:
-Aerospace Industry.
-Transport Industry.
-Computer Industry.
-Telecommunication industry.
-Agriculture industry.
-Construction Industry.
-Education Industry.
-Pharmaceutical Industry.
-Food Industry
-Health Care Industry
-Hospitality Industry
-Entertainment Industry
In the past mining companies were not made responsible for the clean-up of any of the mine sites. As a result, abandoned mines had a severe impact on the environment in Ontario. Which of these is not a result of these mining practices?
1) Chemical reactions producing sulphuric acid decrease soil and water PH in the area.
2) Acid leaching dissolves metals found in the soil thus allowing them to enter the water system.
3) Heavy metals which are left tailing ponds can dissolve and enter the water system.
4) Old and inefficient mining smokestacks contaminate the soils around abandoned mine sites.
Answer:
Old and inefficient mining smokestacks contaminate the soils around abandoned mine sites.
Explanation:
A smokestack, is a very tall channel commonly used in many instances to release gases produced by combustion processes directly into the air. These high towers are aimed at dispersing the gaseous pollutants over a wider area thereby minimizing their impact.
Old and inefficient smokestack do not contaminate the soil since they are very high towers that discharge gases directly into the atmosphere. Hence they are not part of the sources of soil contamination in abandoned mines.
1. All of the following statements are true
regarding spontaneous process, EXCEPT:
A. It occurs without requiring an outside
force.
B. It can be a physical or chemical change
C. It will continue until equilibrium is
reached.
D. It will suddenly stop once products ar
formed.
Which of the following is an example of a
spontaneous process?
A. Melting of ice in room temperature
B. Transfer of heat from a cold objectt
hot object
C. Removing rust on an iron nail
D. Separation of hydrogen and oxygen
atoms via electrolysis
Answer:
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HELP PLSSS WOOT WOOT
What is the value of R in the ideal gas law?
O A. -0.0821 L'atm/mol K
OB. 0.0821 L'atm/mol:K
O c. 273 L'atm/mol K
O D. -273 L'atm/mol K
