Answer:
2-
Explanation:
For an element to be stable, it must follow the octet rule: an atom will gain, lose or share electrons until its valence shell is complete with 8 electrons.
An element with the valence electron configuration ns²np⁴ has 6 (2+4) electrons in its valence shell. Thus, in order to fulfill the octet, it will gain 2 electrons. As a consequence, it will form an anion with charge 2-.
20)
Which substance is an acid?
A)
Ba(OH)2
B)
CH3COOCH3
C)
H3PO4
D)
NaCl
can someone help
Answer:
H3PO4
Explanation:
The H3PO4 is an acid as it release H+ ion when dissolved in a solution and H3PO4 is known as phosphoric acid
which process produces co2?
burning of fossil fuels is the answer
Answer:
burning of fossil fuel
Explanation:
. 500 L of H2 and 400 L of O2 are mixed to produce H2O in a closed container. What volume
of H2O is produced ? Which is the limiting reagent ?
Answer:
may be 700Explanation : What i feel is that the chemical formula is 2 H2 + O2 — 2 H2O
So taking 500 as 2 H2 that the value of O2 reacted will be half of original value that is 200...
The density of water is about 1.0 g/mL at room temperature. Briefly explain how the density of an aqueous solution at room temperature can be significantly less than 1.0 g/mL. Give an example of such a solution.
Answer:
The density of water is about 1.0 g/mL at room temperature.
Briefly explain how the density of an aqueous solution at room temperature can be significantly less than 1.0 g/mL.
Give an example of such a solution.
Explanation:
That means 1.0mL of water weighs ---- 1.0g
If any other aqueous solution which has mass less than 1.0g will have density less than 1.0g.
For example aqueous solution of sulfuric acid has density 0.98g/mL.
That means 1mL of sulfuric acid has mass 0.98g.
Dissolving gases or liquids in water whose density are less than that of water will result in an aqueous solution whose density is less than that of water, for example, sulfuric acid which has a density 0.98g/mL.
What is density of a substance?The density of a substance is the ratio of the mass to the volume of that substance.
Density measures compactness.
More compact substances are more dense.
The density of water is about 1.0 g/mL at room temperature.
This means that 1.0mL of water weighs 1.0g
1.0 mL of an aqueous solution whose mass is less than 1.0g will have density less than that of water.
Dissolving gases or liquids in water whose density are less than that of water will result in an aqueous solution whose density is less than that of water.
An example of an aqueous solution whose density is less than that of water is sulfuric acid which has a density 0.98g/mL.
Sulfuric acid is prepared by dissolving sulphur (vi) oxide, a gas, in water.
This means 1mL of sulfuric acid has mass 0.98g.
Learn more about density at: https://brainly.com/question/406690
Why does glucose and acentic acid have the same empirical formula
Answer:
Examples. Glucose (C6H12O6), ribose (C5H10O5), Acetic acid (C2H4O2), and formaldehyde (CH2O) all have different molecular formulas but the same empirical formula: CH2O.
Explanation:In chemistry, the empirical formula of a chemical compound is the simplest positive integer ratio of atoms present in a compound.
Naturally occurring gallium is a mixture of isotopes
that contains 90.11% of Ga-69 (atomic mass = 68.93
u) and 9.89% of Ga-71 (atomic mass 70.92 u).
What is the average atomic mass of naturally
occurring gallium?
A) 69.93 amu
C) 69.50 amu
B) 69.12 amu
D) 69.00 amu
which of the following experiments raises ethical concerns
Answer:
Research that releases a poisonous gas into the air.
Explanation:
Since I don't know the options I will guess it is ^
A bulb is filled with Hą gas at a temperature T. The pressure is 756 mmHg. A portion of the gas is transferred to a flask and at 100 kPa, occupies 40.0 mL at the same temperature T. The pressure in the original bulb drops to 625 mmHg at temp. T. What is the volume of the bulb? (NOTE: 100 kPA = 750.0 mmHg)
Answer:
The volume of the bulb is 229.0mL
Explanation:
To solve this question we need to use Boyle's law that states that the pressure is inversely proportional to the volume of a gas under constant temperature. in the problem:
P1V1 = P2V2 + P3V1
Where P is pressure and V volume of:
1, initial state of the gas. 2, state of the transferred flask, 3, final state of the gas in the initial bulb
Replacing:
756mmHg*V1 = 750.0mmHg*40mL + 625mmHg*V1
131mmHg*V1 = 30000mmHg*mL
V1 = 229.0mL
The volume of the bulb is 229.0mL
You wash dishes for a chemistry laboratory to make extra money for laundry. You earn 12, and each shift lasts 75. Your laundry requires 12 quarters/load.
A. How many shifts must you work if you wish to wash 10 loads of laundry?
B. How many loads of laundry can you wash if you work 3 shifts?
C. How many loads of laundry will each shift pay for if the cost per load rises to 16 quarters?
Answer:
A. 2 shifts
B. 15 loads of laundry
C. 3.75 loads of laundry
Note: The question is missing some details. A similar complete question is given below:
You wash dishes for a chemistry laboratory to make extra money for laundry. You earn 12 dollars/hour, and each shifts lasts 75 minutes. Your laundry requires 12 quarters/load. How many loads of laundry can you wash if you work 3 shifts? How many loads of laundry will each shift pay for if the cost per load rises to 16 quarters?
Explanation:
The following information is provided :
Amount earned per hour = 12 dollars/hour
Duration for one shift = 75 minutes = 1.25 hours
Cost per load = 12 quarters/load
A. Cost of 10 loads of laundry = 12 × 10 = 120 quarters
120 quarters = 120/4 dollars = 30 dollars
Time taken to earn 30 dollars = 30/12 × 1 hour = 2.5 hours
Number of shifts required in 2.5 hours = 2.5/1.25 = 2 shifts
Therefore, 2 shifts are required to wash 10 loads of laundry
B. Duration of 3 shifts = 1.25 hours × 3 shifts = 3.75 hours
Amount earned in 3 shifts = 3.75 × 12 = 45 dollars
12 quarters/load = 12 × 0.25 dollars = 3 dollars/load
Number of loads that can be washed = 45/3 = 15 loads of laundry
Therefore, 15 loads of laundry can be washed in 3 shifts
C. 16 quarters/load = 16 × 0.25 = 4 dollars/ load
Amount earned per shift = 1.25 × 12 =15 dollars
Loads of laundry per shift = 15/4 = 3.75 loads
Therefore, 3.75 loads will be paid per shift
Sort the following molecules or ions into their proper three-dimensional molecular shapes. Drag the appropriate molecules or ions to their respective bins.
1. NBr3
2. SO2
3. SBr42+
4. SO42+
5. CF3Cl
A. Tetrahedral
B. Trigonal pyramidal
C. Bent
D. Linear
E. Trigonal planar
Answer:
NBr3 - Trigonal pyramidal
SO2- Bent
SBr42+- Tetrahedral
SO42- Tetrahedral
CF3Cl - Tetrahedral
Explanation:
The shape of a molecule depends on the number of electron pairs on the valence shell of the central atom in the molecule. This is well captured in the valence shell electron poair repulsion theory.
The number of electron pairs on the outermost shell of the central atom in a molecule are called regions of electron density. According to this theory, these regions of electron density must be positioned as far apart from each other as possible to minimize repulsions between electron pairs.
This theory is the basis of the shapes of molecules shown in the answer. If a molecule has four regions of electron density, it could be trigonal pyramidal or tetrahedral in shape such as NBr3 and CF3Cl.
Note that, when deciding on the three dimensional geometry of a molecule, only the covalent bonds present are considered.
how to solve the chemical formula for Calcium Chlorate
Answer:
Ca(ClO3)2
Explanation:
The chemical formula of calcium chlorate is Ca(ClO3)2, which means in this molecule, Ca2+ ion is bonded to two ClO3- ions. So the formula can be expended to O3Cl-Ca-ClO3, or CaCl2O6 (basically times the numbers of the elements inside the bracket by the number outside the bracket.
what is an example of reactivity?
jessica is a crime scene investigator studying a breech face mark where is the breech face mark located
Answer:
on the back of the firing pin
Explanation:
Balance the following equation and list the coefficients in order from left to right.
SF4 + __ H2O → _H2SO3 + HE
Vascular tissue
From Wikipedia, the free encyclopedia
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Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem.
Detail of the vasculature of a bramble leaf.
Translocation in vascular plants
This article is about vascular tissue in plants. For transportation in animals, see Circulatory system.
Vascular tissue is a complex conducting tissue, formed of more than one cell type, found in vascular plants. The primary components of vascular tissue are the xylem and phloem. These two tissues transport fluid and nutrients internally. There are also two meristems associated with vascular tissue: the vascular cambium and the cork cambium. All the vascular tissues within a particular plant together constitute the vascular tissue system of that plant.
The cells in vascular tissue are typically long and slender. Since the xylem and phloem function in the conduction of water, minerals, and nutrients throughout the plant, it is not surprising that their form should be similar to pipes. The individual cells of phloem are connected end-to-end, just as the sections of a pipe might be. As the plant grows, new vascular tissue differentiates in the growing tips of the plant. The new tissue is aligned with existing vascular tissue, maintaining its connection throughout the plant. The vascular tissue in plants is arranged in long, discrete strands called vascular bundles. These bundles include both xylem and phloem, as well as supporting and protective cells. In stems and roots, the xylem typically lies closer to the interior of the stem with phloem towards the exterior of the stem. In the stems of some Asterales dicots, there may be phloem located inwardly from the xylem as well.
Between the xylem and phloem is a meristem called the vascular cambium. This tissue divides off cells that will become additional xylem and phloem. This growth increases the girth of the plant, rather than it
Write a balanced nuclear equation for the following: The nuclide astatine-218 undergoes alpha emission to give bismuth-214
____________ → _______ + __________
Answer:
[tex]^{218}_{85}At\rightarrow ^{214}_{83}Bi+^{4}_{2}He[/tex]
Explanation:
Hello there!
In this case, since the radioactive reaction for the alpha emission of astatine-218 to bismith-214 involve the release of a helium atom as shown below:
[tex]^{218}_{85}At\rightarrow ^{214}_{83}Bi+^{4}_{2}He[/tex]
Whereas the atomic number decreases by 2 and the mass number by 4 in agreement to the release of the Helium atom.
Regards!
19. A girl is ice skating and has 35 kgm/s of momentum. After she bumps into a
friend, she has 25 kgm/s of momentum. How much did she give her friend?
Answer:
15 kgm/s of momentum
Explanation:
4 AlF3 + 3 O2 ----------> 2Al2O3 + 6 F2
How many moles of AlF3 is needed to produce 8.25 moles of F2 from the given balanced equation shown above? (SHOW WORK)
Explanation:
6 F2------->4 AlF3
F2-----------> 4/6 AlF3
8.25 F2 ---------> 4×8.25/6 AlF3
so 5.5 moles
Washes and extractions are both techniques that use a separatory funnel to separate liquid layers. However, washes and extractions have differences. Determine whether each statement applies to washes or extractions.
Leaves impurities in their starting layer Choose...
Moves impurities from one layer to another Choose...
Moves desired compound from one layer to another Choose...
Often involves a reaction in one of the layers Choose...
Leaves desired compound in its starting layer Choose...
Answer:
Leaves impurities in their starting layer - Extraction Moves impurities from one layer to another - Wash Moves desired compound from one layer to another - Extraction Often involves a reaction in one of the layers - Extraction Leaves desired compound in its starting layer - WashExplanation:
Both extraction and wash are technical materials separation processes. Both seek to carry out a separation of liquid-liquid, through the relationship between solvent and solute present in this solution. Both use a separation funnel and are very similar processes where the main difference is the purpose that each one seeks to exercise. The extraction causes the dissolution of the material that the researcher wants to leave behind. this process leaves impurities in the initial solution layer and moves the researcher's desired compound to the second layer of solution. A chemical reaction can take place during this process.
A wash, on the other hand, dissolves all impurities from the solution and extracts the compound desired by the researcher. Therefore, we can conclude that during this process the impurities are moved from one layer to another in the solution until it is discarded from the funnel, leaving the desired compound in the initial layer.
True or False: Photosynthesis can take place under water.
True
False
Answer:
True
Explanation:
hope this helps mate
A concentration cell is constructed by using the same half-reaction for both the cathode and anode. What is the value of standard cell potential, for a concentration cell that combines a silver anode in contact with 0.10 M silver nitrate and a silver cathode in contact with 0.00003 M silver nitrate
Solution :
A cell that is concentrated is constructed by the same half reaction for the anode as well as he cathode.
We know,
In a standard cell,
the reduction half cell reaction is :
[tex]$Ag^+(aq)+e^- \rightarrow Ag(s) E^0 = -0.80 \ V$[/tex]
The oxidation half ell reaction :
[tex]$Ag(s) \rightarrow Ag^+(aq) + e^- \ E^0= +0.80 \ V$[/tex]
Thus the complete reaction of the cell is :
[tex]$Ag^+(aq)+ Ag(s) \rightarrow Ag^+(aq)+Ag(s)$[/tex]
[tex]$E^0 $[/tex] cell = [tex]$E_R - E_L = 0.00 \ \text{volts}$[/tex]
Studying and got stuck if someone can help me.
Answer:
Ph level 0-7 is a acid
ph level 7-14 is base
bases turn paper blue
acids dissolve metal
acids contain hydrogen ions
Explanation:
I dont know the last one all I know that they become neutral when acids and bases are mixed.
The diagram shows an experiment. damp litmus paper gas given off mixture of ammonium chloride and sodium hydroxide 1 heat What is the name of the gas and the final colour of the litmus paper? gas colour A ammonia blue B ammonia red с chlorine white D chlorine red plz guys help me
Answer:
The correct answer is - A. ammonia blue.
Explanation:
It is given that there is a mixture of ammonium chloride and sodium hydroxide and if we heat the Mixture of NH4Cl and NaOH then, the following reaction will take place-
NH4Cl (aq)+ NaOH (aq)==> NaCl (aq) + NH3 (g)+ H2O (l)
In this reaction, there is a release of NH3 gas which is absorbed on litmus paper. We know that NH3 gas is basic in nature and so it will turn litmus paper blue.
Thus, the correct answer would be - NH3 (ammonia ) and Blue
If atoms of helium, neon, argon and krypton gas are moving at the same speed, which atom would have the highest kinetic energy
Helium atom would have the highest kinetic energy.
What is Kinetic Energy ?
Kinetic energy is a form of energy that a gas has by reason of its motion.
If work, which transfers energy, is done on a gas by applying a net force, the gas speeds up and thereby gains kinetic energy
Different gas particles move at different speeds with there definite kinetic energy—gases with smaller particles tend to be moving faster at the same temperature, which means they have a higher speed.
Helium is the smallest particles and thus, it will be the gas with the highest speed.
Learn more about Kinetic energy here ;
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Which statements explain the relationship between photosynthesis and cellular respiration? Select two options.
The glucose that plants use for energy is made by animals in cellular respiration.
Glucose is a reactant in both photosynthesis and cellular respiration
The oxygen released by photosynthesis is breathed in by animals to break down glucose.
Carbon dioxide is a product of both photosynthesis and cellular respiration
The carbon dioxide released by animals is used to build glucose in photosynthesis.
Answer:
the 2nd and 5th
Explanation:
they are both correct
Answer:
b and d | Glucose is a reactant in both photosynthesis and cellular respiration. | Carbon dioxide is a product of both photosynthesis and cellular respiration.
Explanation:
hope this helps.
Which equation represents a neutralization reaction? 1. Ca(OH) 2 Ca^ 2+ +2OH^ - 2. CaCl 2 Ca^ 2+ +2Cl^ - 3 H^ + +OH^ - HOH 4. H^ + +F^ - HF
NaCl and HCl both have chlorine but are different types of bonds.
What kind of bonds are each of these?
What evidence did you use to determine what types of bonds they are?
Answer:
In HCl ,bond between hydrogen and chlorine is covalent. But due to difference in electronegativity of hydrogen and chlorine,shared electron pair gets attracted towards chlorine. Due to this polar covalent
Help guys please question 3 in picture ASAP pls
Answer:
1 Spinal fluid
2 Milk
3 Saliva
4 Urine
5 Gastric content
Explanation:
Hello there!
In this case, according to the given information, it turns out firstly necessary for us to calculate the pH of both gastric content and spinal fluid by using the following equations and works:
[tex]pH_{gastric}=-log(10^{-2})=2.0\\\\pH_{spinal}=14+log(10^{-6.6})=7.4[/tex]
Thus, we rank them as follows:
1 Spinal fluid
2 Milk
3 Saliva
4 Urine
5 Gastric content
Regards!
An eccentric chemistry professor (not mentioning any names) stops in every day and orders 200ml of Sumatran coffee at precisely 75.0°C. You then need to add enough milk at 5.00°C to drop the temperature of the coffee, initially at 95.0°C, to the ordered temperature.
Answer:
68.97g of milk must be added
Explanation:
To solve this problem we need to use the equation:
Q = C*m*ΔT -Coffee cup calorimeter equation-
This equation relates mass and change in temperature with heat of solution, Q.
The energy that decreases in the milk is the same that increases in the milk. That is:
Q(milk) = Q(tea)
Using the equation:
4.184J/molK* Mass milk * (65.0°C - 7.00°C) = 4.184J /molK * 200g (Tea) * (85.0°C - 65.0°C)
Mass milk * 58.0°C = 200g * 20.0°C
Mass milk = 4000g°C / 58.0°C
Mass milk =
68.97g of milk must be added
Phenols do not exhibit the same pka values as other alcohols; they are generally more acidic. Using the knowledge that hydrogen acidity is directly related to the stability of the anion formed, explain why phenol is more acidic than cyclohexane
Answer:
Phenols do not exhibit the same pka values as other alcohols;
They are generally more acidic.
Using the knowledge that hydrogen acidity is directly related to the stability of the anion formed, explain why phenol is more acidic than cyclohexane.
Explanation:
According to Bromsted=Lowry acid-base theory,
an acid is a substance that can release [tex]H^{+}[/tex] ions when dissolved in water.
So, acid is a proton donor.
If the conjugate base of an acid is more stable then, that acid is a strong acid.
In the case of phenol,
the phenoxide ion formed is stabilized by resonance.
[tex]C_6H_5OH -> C_6H_5O^- +H^+[/tex]
The resonance in phenoxide ion is shown below:
Whereas in the case of cyclohexanol resonance is not possible.
So, cyclohexanol is a weak acid compared to phenol.
Calculate the number of milliliters of 0.666 M Ba(OH)2 required to precipitate all of the Pb2 ions in 163 mL of 0.656 M Pb(NO3)2 solution as Pb(OH)2. The equation for the reaction is:
Pb(NO3)2(aq) Ba(OH)2(aq) Pb(OH)2(s) Ba(NO3)2(aq)
Answer:
161 mL
Explanation:
Pb(NO₃)₂(aq) + Ba(OH)₂(aq) → Pb(OH)₂(s) + Ba(NO₃)₂(aq)First we calculate how many Pb⁺² moles reacted, using the given concentration and volume of the Pb(NO₃)₂ solution:
163 mL * 0.656 M = 107 mmol Pb(NO₃)₂As 1 millimol of Pb(NO₃)₂ would react with 1 millimol of Ba(OH)₂, to precipitate 107 mmoles of Pb(NO₃)₂ we would require 107 mmoles of Ba(OH)₂.
Using the number of moles and the concentration we can calculate the required number of milliliters:
0.666 M = 107 mmol / x mLx mL = 161 mL