Answer: bromine
Explanation:
There are a total of 2+2+6+2+6+2+10+5=35 electrons, meaning there are 35 protons. The element with atomic number 35 is bromine
Assertion (A): Naphthalene balls disappear with time without leaving any solid.
Reason (R): Solid converted to liquid is called sublimation.
a) Both A and R are true and R is the correct
explanation of A.
b) Both A and R are true but R is not the
correct explanation of A.
c) A is true but R is false. d) A is false but R is true.
Explanation:
a) Both A and R are true and R is the correct
explanation of A.
Answer:
[tex]\fbox {c) A is true but R is false.}[/tex]
Explanation:
Assertion (A):
⇒ Naphthalene balls disappear with time without leaving any solid.
⇒ True √
Reason (R):
⇒ Solid converted to liquid is called sublimation.
⇒ False ×
⇒ Solid converted to liquid is called melting
8.0 mol AgNO3 reacts with 5.0 mol Zn in
a single replacement reaction.
2AgNO3 + Zn → 2Ag + Zn(NO3)2
How many moles of Ag form from 8.0
mol AgNO3?
[?] mol Ag
Round your answer to the tenths place.
Taking into account the reaction stoichiometry, 8 moles of Ag can be produced from 8 moles of AgNO₃ and 5 moles of Zn.
Reaction stoichiometryIn first place, the balanced reaction is:
2 AgNO₃ + Zn → 2 Ag + Zn(NO₃)₂
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
AgNO₃: 2 moles Zn: 1 mole Ag: 2 moles Zn(NO₃)₂: 1 moleLimiting reagentThe limiting reagent is one that is consumed first in its entirety, determining the amount of product in the reaction. When the limiting reagent is finished, the chemical reaction will stop.
Limiting reagent in this caseTo determine the limiting reagent, it is possible to use a simple rule of three as follows: if by stoichiometry 1 mole of Zn reacts with 2 moles of AgNO₃, 5 moles of Zn reacts with how many moles of AgNO₃?
[tex]amount of moles of AgNO_{3}= \frac{5 moles of Znx2 moles of AgNO_{3}}{1 mole of Zn}[/tex]
amount of moles of AgNO₃= 10 moles
But 10 moles of AgNO₃ are not available, 8 moles are available. Since you have less moles than you need to react with 5 moles of Zn, AgNO₃ will be the limiting reagent.
Moles of Ag formedConsidering the limiting reagent, the following rule of three can be applied: if by reaction stoichiometry 2 moles of AgNO₃ form 2 moles of Ag, 8 moles of AgNO₃ form how many moles of Ag?
[tex]amount of moles of Ag=\frac{8 moles of AgNO_{3}x2 moles of Ag }{2 moles of AgNO_{3}}[/tex]
amount of moles of Ag= 8 moles
Then, 8 moles of Ag can be produced from 8 moles of AgNO₃ and 5 moles of Zn.
Learn more about the reaction stoichiometry:
brainly.com/question/24741074
brainly.com/question/24653699
#SPJ1
Instructions: In this virtual lab, you will use a virtual spectrometer to analyze astronomical bodies in space. Record your hypothesis and spectrometric results in the lab report below. You will submit your completed report to your instructor.
The main function of using a virtual spectrometer in order to analyze astronomical bodies in space is to find the chemical composition of planets and stars.
What is a Virtual Spectrometer?This refers to the instrument that is used to observe the color separation of light in a controlled experiment.
Hence, we can see that another reason for the use of a virtual spectrometer to make an analysis of astronomical bodies is to indicate the speed and direction of a star or galaxy as it spreads incoming beams of light into different spectrums.
Read more about virtual spectrometers here:
https://brainly.com/question/21578855
#SPJ1
Which two types of waves can transmit energy through a vacuum?
Answer:
electromagnetic waves and mechanical waves
Explanation:
I think these two kinds of waves can transmit energy through a vaccume.
Hope I helped!
Electromagnetic waves.
Gravity waves.
What is the lowest energy level that contains d orbitals.
Answer:
3
Explanation
it is 3
The pressure of Cl2 gas in a 2.0-L cylinder is 300. kPa at 25°C. What is the pressure (in kPa) when this gas is released into a 100-L chamber at 25°C? ______ kPa
The Final Pressure of the gas is 6 kPa
What is Boyle's Law ?At constant Temperature , the absolute pressure exerted by the gas is inversely proportional to the volume of the gas.
[tex]\rm P_1V_1 = P_2V_2[/tex]
It is given that
[tex]\rm P_1 = 300k.Pa\\T_1 = 25 \; Degree\\V_1 = 2L\\V_2 = 100L\\T_2 = 25 Degree\\P_2 = ?[/tex]
To determine Final Pressure , Boyle's Law will be applied
300 * 2 = P₂ * 100
P₂ = 300 * 2 / 100
P₂ =6 kPa
Therefore the Final Pressure of the gas is 6 kPa.
To know more about Boyle's Law
https://brainly.com/question/1437490
#SPJ1
Reduction of 9-fluorenone: objective of this lab was to reduce 9-fluorenone (a ketone), to 9-fluorenol (an alcohol) using sodium borohydride as the reducing agent. experimental data: 9-fluorenone: mw 180.20 g/mol mass used 0.6 grams methanol: mw 32.04 g/mol volume used: 6ml density: 0.792 nabh4: mw 37.83 g/mol mass used 0.05 grams 9-fluorenol: mw 182.22 g/mol balanced equation for the reaction is: 4c13h8o nabh4 4ch3oh --> 4c13h10o nab(och3)4 calculate the potential yield (in grams) of 9-fluorenol for 9-fluorenone, methanol and nabh4. from these potential yields identify the limiting reagent and theoretical yield.
9-fluorenone is a limiting reagent and theoretical yield.
What is 9-fluorenol?Fluoren-9-ol is a member of the class of hydroxyfluorenes that is 9H-fluorene substituted by a hydroxy group at position 9.
Inspect stoichiometry of the given reaction as per the balanced equation below:
[tex]4C_{13}H_8O + NaBH_4 + 4CH_3 OH[/tex] → [tex]4C _{13} H _{10} O + NaB(OCH_3 )_4[/tex]
Given weight:
0.6 grams methanol
0.05 grams 9-fluorenol
0.792 [tex]NaBH_4[/tex]
Out of the three reactants, [tex]NaBH_4[/tex] acts as a reducing agent only and hence the reaction can occur only when [tex]NaBH_4[/tex] is present in relatively much smaller amounts. But the yield of the product,9-fluorenol, is not governed by its quantity.
Theoretically, when equimolar amounts of reactants ( 9-fluorenone and methanol ) are taken for reaction in presence of [tex]NaBH_4[/tex] an equivalent quantity of product, 9- fluorine is obtained, as inspected in the above stoichiometric relations. But practically we have used a lesser number of moles of 9-fluorenone than theoretically needed, hence in this case it should serve as the limiting reagent.
9- fluorenone, methanol & [tex]NaBH_4[/tex] are the reactants, while the product 9-fluorenol would be obtained = 0.0033 moles
This would represent the theoretical yield of the product 9-fluorenone, as we have used an excess of methanol thus facilitating the reaction to go to completion.
Hence, 9-fluorenone is a limiting reagent.
Learn more about the 9-fluorenol here:
https://brainly.com/question/6798923
#SPJ1
how to minimize the harmful effects of power station on our environment
I will give a brainley Hi guys I need help figuring out where the moderately reactive atoms are located on the periodic table and how the number of balance electrons of the light metals compared to those heavier than born
The moderately reactive atoms located in the periodic table are fluorine, chlorine, bromine, and iodine which means the halogens family.
The number of balance electrons of the light metals compared to those heavier by listing elements in the order of increasing atomic number.
What are halogen metals?They are the five non-metals in family 7A of the periodic table. Halogens are chemical elements that form inorganic salts. In the periodic table they are part of group 17 or family 7A.
Halogens are strong oxidants and react mainly with alkali metals (Family I A) which tend to donate an electron. They also react with metals and noble gases (Family VIII A).
The chemical elements are arranged from left to right and top to bottom in order of increasing atomic number, or the number of protons in an atom's nucleus, which generally coincides with increasing atomic mass.
See more about halogens at:
brainly.com/question/11156152
#SPJ1
[tex]\begin{gathered}\\ \underline{\boxed{\large\leadsto\frak \red{ Answer :- }}} \\ \end{gathered}[/tex]
The moderately reactive atoms located in the periodic table are fluorine, chlorine, bromine, and iodine which means the halogens family.The number of balance electrons of the light metals compared to those heavier by listing elements in the order of increasing atomic number.What are halogen metals?
They are the five non-metals in family 7A of the periodic table. Halogens are chemical elements that form inorganic salts. In the periodic table they are part of group 17 or family 7A.Halogens are strong oxidants and react mainly with alkali metals (Family I A) which tend to donate an electron. They also react with metals and noble gases (Family VIII A).The chemical elements are arranged from left to right and top to bottom in order of increasing atomic number, or the number of protons in an atom's nucleus, which generally coincides with increasing atomic mass.▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
what happens when you mix an element into a solution with lesser reaction?
When an element is placed into a solution with lesser reaction, the reaction rate will be slow.
What is rate of a reaction?The rate of a reaction is the rate which reactants molecules are converted or the products molecules are formed.
The rate of a reaction increases with increase in concentration of the reactants and decreases with decrease in concentration.
Therefore, when an element such as a metal is placed in solution of low concentration such as very dilute acid, the reaction rate will be slow.
Learn more about rate of reaction at: https://brainly.com/question/24795637
#SPJ12
Question 3
Not yet
answered
Points out of
If you dissolve 2.70 g of NaCl in 425 mL of water, what is the molarity of the
solution? (Report your answer to three places past the decimal point. Moodle is
looking for a number only, no units.)
Answer: 0.118M
Explanation:
The formula for molarity is: [tex]M=\frac{mol solute}{L solution}[/tex]
First, we need to find the number of moles of NaCl.
[tex]2.70gNaCl*\frac{1molNaCl}{58.44gNaCl} =0.05molNaCl[/tex]
Next, we must convert millimeters to liters. We can do that by dividing the number of mL by 1000.
[tex]\frac{425mL}{1000} =0.425L[/tex]
Now we have our needed data! All we need to do now is plug in our data to the molarity formula.
[tex]M=\frac{0.05mol}{0.425L} =0.118M[/tex]
I hope this helps! Pls mark brainliest!! :)
You examine an ice core sample from 10,000 years ago when global temperatures were unusually high. Based upon past studies and insights from current GHG levels, we expect that atmospheric levels of carbon dioxide Group of answer choices were high but methane levels were low. and methane were unusually low. and methane were unusually high. were low but methane levels were high.
Methane was unusually high is the correct option. Hence, option B is correct.
What is methane?Methane is the simplest member of the paraffin series of hydrocarbons and is among the most potent greenhouse gases. Its chemical formula is [tex]CH_4[/tex].
As the ice compacts over some time, tiny bubbles of the atmosphere or surroundings including greenhouse gases like carbon dioxide and methane—press inside the ice. These air pocket “fossils” give samples of what the atmosphere was kind when that layer of ice formed.
Based upon past studies and insights from current GHG levels, we assume that atmospheric levels of carbon dioxide and methane were unusually low.
Learn more about methane here:
https://brainly.com/question/2127750
#SPJ1
Which component or condition of a reaction affects the rate of the reaction but is not consumed during the course of the reaction?.
Answer:
A catalyst is a substance that can be added to a reaction to increase the reaction rate without getting consumed in the process.
Explanation:
Answer:
Catalyst
Explanation:
What volume of a 4.13 M lithium
nitrate solution would be needed tomake 195 mL of a 1.05 M solution
by dilution?
[?] L LINO3
I’ll give u 100 points if ur answer is correct
Answer:
0.0496
Explanation:
Well, there’s none!!! It’s just so easy…
Answer: 49.6
Explanation: It actually wants the answer it mL not L.
When a scientific theory has been tested and proved by the scientific community, it becomes a law.
True
False
Answer:
False
Explanation:
Because laws and theories are developed for different purposes, laws never become theories, and theories do not become laws.
the company calculated that they would produce 4.8 tonnes of magnesium but only 3.2 tonnes was produced calculate the percentage yield
Why do you need to combust benzoic acid before testing the "unknown" sample you are interested in? Why do you need to combust more than one sample of the "unknown" you are testing?
Various samples of the must be combusted in other to obtain a reliable result.
What is a bomb calorimeter?The bomb calorimeter is used to obtain the energy of a sample. This is called the energy equivalent or the energy value of the sample.
Now, we know that the bomb calorimeter is calibrated by the use of benzoic acid hence it must be combusted first to obtain the basic energy value of the calorimeter.
Various samples of the must be combusted in other to obtain a reliable result.
Learn more about bomb calorimeter:https://brainly.com/question/24245395?
#SPJ1
Why did potato chunks a, b, and c gain mass here?
The most likely reason why the potato chunks gained mass is that water entered the potato cells.
How does water enter potato cells?The process of Osmosis allows water to pass through the semi-permeable membrane of potato cells.
This happens when the potato cells have less water than the material around them which then leads to water entering the cells to balance the water concentration.
The potato cells will expand and have more mass as a result.
Find out more on osmosis at https://brainly.com/question/2625460.
#SPJ12
You mass two substances. One substance has a mass of 22.45 g and the other has a mass of 3.1 g. What is the total mass of both objects?
Answer:
25.55 g
Explanation:
To find the total mass of both objects, you need to add the masses together.
22.45 g + 3.1 g = 25.55 g
In correct significant figures (2 sig figs to match 3.1 g), the value would be 26 g.
Answer:
answer = 25.55
Explanation:
You just have to add the mass of the two objects
What is the molar concentration of
a solution with a volume of 1.5 L
containing 660 g Ca3(PO4)2?
Answer:
1.42 M
Explanation:
First calculate the amount of moles.
that's done by dividing the mass with the molecular mass so 660g / 310.18 g/mol = 2.13 mol
Then you can calculate the molarity by dividing the moles with the volume so 2.13 mol / 1.5 l = 1.42 M
(without rounding: 1.418531175 M)
Answer:
1.42 M
Explanation:
Acellus
10.5 mL of an unknown solution are diluted to 80.0 mL. The concentration of the
new solution was determined to be 0.172 M. What was the molarity of the
unknown solution? (Report your answer to two places past the decimal point.
Moodle is looking for a number only, no units.)
Taking into account the definition of dilution, the molarity of the unknown solution is 0.133 M.
DilutionDilution is the process of reducing the concentration of solute in solution, which is accomplished by simply adding more solvent to the solution at the same amount of solute.
In a dilution the amount of solute does not change, but as more solvent is added, the concentration of the solute decreases, as the volume (and weight) of the solution increases.
A dilution is mathematically expressed as:
Ci×Vi = Cf×Vf
where
Ci: initial concentrationVi: initial volumeCf: final concentrationVf: final volumeInitial concentrationIn this case, you know:
Ci= ?Vi= 10.5 mLCf= 0.172 MVf= 80 mLReplacing in the definition of dilution:
Ci× 10.5 mL= 0.172 M× 80 mL
Solving:
Ci= (0.172 M× 80 mL)÷ 10.5 M
Ci= 0.133 M
In summary, the molarity of the unknown solution is 0.133 M.
Learn more about dilution:
brainly.com/question/6692004
brainly.com/question/16343005
brainly.com/question/24709069
#SPJ1
Which of the following best describes a mixture? A. A substance that results when another substance is separated into its component parts B. A substance composed of two or more elements chemically combined C. A substance that results when two or more substances combine physically but not chemically D. A particle consisting of two or more atoms chemically combined
Answer: C. A substance that results when two or more substances combine physically but not chemically
How much sodium bicarbonate to raise alkalinity in pool.
Answer:
A rule of thumb is that 1.5 lbs. of baking soda per 10,000 gallons of water will raise alkalinity by about 10 ppm. If your pool's pH is tested below 7.2, add 3-4 pounds of baking soda. If you're new to adding pool chemicals, start by adding only one-half or three-fourths of the recommended amount.
Webb has calculated the percent composition of a compound. How can he check his result?
After balancing the chemical equation what are the coefficients for these compounds
The cofficient of the [tex]\rm H_2S,HNO_3,NO,H_2O,S[/tex] willl be 3,2,2,4 and 3 respectively.
What is a chemical reaction?One or more compounds, known as reactants, are transformed into one or more distinct substances, known as products. Such a process is known as a chemical reaction.
The overall reaction is found as;
[tex]\rm H_2S +HNO_3 \rightarrow S+NO+H_2O[/tex]
Reduction reaction;
[tex]\rm N^{+5} + 3e^{-1} \rightarrow N^{+2}[/tex]
The oxidation half-reaction from the overall reaction is;
[tex]\rm S^{-2} = S+ 2e^{-1}[/tex]
Multiply the oxidation reaction by 2 and the reduction reaction by 3 and add them.
[tex]\rm 2 N^{+5}+6e^{-1}+3S^{-2} \rightarrow 2N^{+2}+3S+H_2O \\\\ 2N^{+5}+3 S^{-2}\rightarrow 2N^{+2}+3S \\\\ 3H_2S +2HNO_3 \rightarrow 3 S + 2NO + 4H_2O[/tex]
The cofficient of the [tex]\rm H_2S,HNO_3,NO,H_2O,S[/tex] willl be 3,2,2,4 and 3 respectively.
To learn more about the chemical reaction refer to the link;
https://brainly.com/question/22817140
#SPJ1
Which of the following is the best definition of a chemical change?
A. A change in a substance where one or more new substances form
B. A change in a substance where no new substance forms
C. A change in a substance where energy is conserved
OD. A change in a substance where a phase change occurs
Answer:A is correct
Explanation:
increasing the airplane's speed or wing size does which of the following
a) decreases the amount of drag on the plane
b) increases the gravitational pull on the pane
c) generates more lifting force
d) creates a sonic boom
Answer:
increases the gravitional pull on tge pane
Answer:
generates more lifting on the plane
Explanation:
A sample of pure nitrogen has a temperature of 15°c. What is the temperature of the nitrogen in units of kelvin?
The temperature of the nitrogen in units of kelvin is 288 kelvin
How to convert the temperature of nitrogen from degree Celsius to kelvin?The sample of pure nitrogen has a temperature of 15 degree Celsius.
Let's convert the temperature from degree Celsius to kelvin.
K = C + 273
where
K = temperature in kelvinC = temperature in degree Celsius.Therefore,
K = 15 + 273
K = 15 + 273
K = 288 kelvin
learn more on nitrogen here: https://brainly.com/question/13870292
#SPJ12
What volume of a 3.95 M
potassium chloride solution would
be needed to make 325 mL of a
2.76 M solution by dilution?
[?] mL of 3.95 M KCl
0.227L is the volume of a 3.95 M potassium chloride solution that would be needed to make 325 mL of a 2.76 M solution by dilution.
What are moles?A mole is defined as 6.02214076 × 10^{23} of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.
Moles of KCl in new solution
0.325dm³ x (2.76mol/dm³)
= 0.897mol.
Hence volume needed
0.897mol ÷(3.95mol/dm³)
= 0.227dm³ or 0.227L.
Learn more about moles here:
https://brainly.com/question/8455949
#SPJ1
45.8 grams of copper requires 1172 J of heat to reach a final temperature of 100.5 ℃. What was the initial temperature? Specific heat of copper is 0.385 J/g℃.
A. 66.5[?][?][?]
B. 122[?][?][?]
C. 34.0[?][?][?]
D. 75.2[?][?][?]
I also have no idea what the [?][?][?] is. Can someone please help me for 20 points? I desperately need help. No nonsense answers either, and show the steps pls. :')
Answer:
Option A, 66.5
Explanation:
use q (heat) = m(mass) * cp(specific heat) * deltat (change in temp)
q= 1172, m = 45.8, cp = 0.385
1172= (45.8) * (0.385) * Delta T
1172= 17.633 *DeltaT
1172/17.633 =DeltaT
66.5 =DeltaT
