How does an anion form?
A. An anion forms when a stable atom loses one or more neutrons.
B. An anion forms when a stable atom loses one or more protons.
C. An anion forms when a stable atom gains one or more electrons.
D. An anion forms when a stable atom loses one or more electrons.

Answers

Answer 1
Answer:a is the answer

Related Questions

What is the most highly populated rotational level of Cl2 (i) 25deg C and (ii) 100 deg C? Take B=0.244cm-1.This question should not be resubmitted, it is a textbook question from the Atkins physical chemistry txtbook. 10 e.

Answers

Answer:

i

[tex]J_{m} = 20 [/tex]

ii

[tex]J_{m} = 22.5 [/tex]

Explanation:

From the question we are told that

  The first temperatures is [tex]T_1 =  25^oC =  25 +273 =298 \ K[/tex]

   The second temperature is  [tex]T_2 =  100^oC =  100 +273 = 373 \ K[/tex]

Generally the equation for  the most highly populated rotational energy level is mathematically represented as

     [tex]J_{m} = [ \frac{RT}{2B}]  ^{\frac{1}{2} } - \frac{1}{2}[/tex]

Here R is the gas constant with value [tex]R =8.314 \ J\cdot K^{-1} \cdot mol^{-1}[/tex]

Also  

      B is given as [tex]B=\ 0.244 \ cm^{-1}[/tex]

   Generally the energy require per mole to move 1 cm is  12 J /mole

So   [tex]0.244 \ cm^{-1}[/tex]  will require x J/mole

           [tex]x =  0.244 *  12[/tex]

=>          [tex]x =  2.928 \ J/mol [/tex]

So at the first temperature

     [tex]J_{m} = [ \frac{8.314 * 298  }{2*  2.928 }]  ^{\frac{1}{2} } - 0.5 [/tex]

=>  [tex]J_{m} = 20 [/tex]

So at the second temperature

           [tex]J_{m} = [ \frac{8.314 * 373  }{2*  2.928 }]  ^{\frac{1}{2} } - 0.5 [/tex]

=>  [tex]J_{m} = 22.5 [/tex]

HELP FAST PLZ!!!!! Which phase change allows a substance to transform from a liquid to a
gas?
melting
Ofreezing
O ionization
condensation
deionization
O
evaporation
sublimation

Answers

Answer:evaporation

Explanation:

Answer:

Pretty sure its evaporation, if its not I'm very sorry.

The ion with the smallest diameter is ________. The ion with the smallest diameter is ________. Be2 Sr2 Ca2 Ba2 Mg2

Answers

Answer:

Be2^+

Explanation:

Ionic diameter increases down the group. This implies that Be2^+ will have the smallest diameter.

This extremely small diameter makes Be2^+ to differ considerably from other ions of group 2 elements.

For instance, the compounds of beryllium are mostly covalent in nature.

An increase in temperature results in A) a decrease in the required activation energy while the reaction rate remains constant. B) an increase in reaction rate due to a decrease in the kinetic energy of the reactants. C) an increase in the rate of reaction because reactant molecules collide with greater energy. D) an increase in both the reaction rate and activation energy due to increased kinetic energy.

Answers

Answer:

C) an increase in rate of reaction because reactant molecules collide with greater energy

Explanation:

Temperature is one of the factors that affect the rate of a reaction. The rate of a reaction increases with an increase in temperature and vice versa. When the temperature of a reaction increases, the kinetic energy of the reactant molecules increases causing them to react at a faster rate.

The reactant molecules respond to an increase in temperature by colliding at a faster rate due to an increased kinetic energy between the reactant molecules.

Which element will gain three electrons to form an anion?
A. aluminum
B. chromium
C. iron
D. nitrogen

Answers

Answer:

D represents the element nitrogen which will gain three valence electrons forming a 3 ion.

Answer:

answer is

Explanation:

D

For the combustion of methane presented in Example 5.4, the chemical reaction is CH4 +2O2 →CO2 +2H2O Suppose that methane flows into a burner at 30 gmol/s, while oxygen flows into the same burner at 75 gmol/s. If all the meth- ane is burned and a single output stream leaves the burner, what is the mole fraction of CO2 in that output stream? Hint 1: Does the fact that all the methane is burned mean that all the oxygen is burned also? Hint 2: Find the molar flow rate of each component gas in the outlet gas ("flue gas").

Answers

Answer:

[tex]x_{CO_2}^{out} =0.25[/tex]

Explanation:

Hello.

In this case, for the reactive scheme, it is very convenient to write each species' mole balance as shown below:

[tex]CH_4:f_{CH_4}^{out}=f_{CH_4}^{in}-\epsilon \\\\O_2:f_{O_2}^{out}=f_{O_2}^{in}-2\epsilon\\\\CO_2:f_{CO_2}^{out}=\epsilon\\\\H_2O:f_{H_2O}^{out}=2\epsilon[/tex]

Whereas [tex]\epsilon[/tex] accounts for the reaction extent. However, as all the methane is consumed, from the methane balance:

[tex]0=f_{CH_4}^{in}-\epsilon \\\\\epsilon=30gmol/s[/tex]

Thus, we can compute the rest of the outlet mole flows since not all the oxygen is consumed as it is in excess:

[tex]f_{O_2}^{out}=f_{O_2}^{in}-2\epsilon=75gmol/s-2*30gmol/s=15gmol/s\\\\f_{CO_2}^{out}=15gmol/s\\\\f_{H_2O}^{out}=2*15gmol/s=30gmol/s[/tex]

It means that the mole fraction of carbon dioxide in that output is:

[tex]x_{CO_2}^{out}=\frac{15}{15+15+30} =0.25[/tex]

Best regards.

Three colorless solutions in test tubes, with no labels, are in a test tube rack on the laboratory bench. Lying beside the tests tubes are three labels : 0.10 M Na2CO3, 0.10 M HCL, and 0.10 M KOH. You are to place the labels on the test tubes using only the three solutions present. Here are your tests:
A few drops of the solutions from test tube 1 added to a similar volume of the solution in test tube 2 produces no visible reaction but the solution becomes warm.
A few drops of the solution from test tube 1 added to a similar volume of the solution in test tube 3 produces carbon dioxide gas.
Identify the labels for test tubes 1, 2, and 3

Answers

Answer:

Test tube 1  0.10 M HCL

Test tube 2  0.10 M KOH

Test tube 3 0.10 M Na2CO3

Explanation:

From the question we are told that

    A few drops of the solutions from test tube 1 added to a similar volume of the solution in test tube 2 produces no visible reaction but the solution becomes warm

Generally this warmth is as a result of a reaction between an acid and a base and the acid is 0.10 M HCL and the base is  0.10 M KOH , the heat generated is know as the heat of neutralization,

The reaction is  

       [tex]HCl_{(aq)} + KOH_{(aq)} \rightarrow KCl_{(aq)} + H_2O_{(l)} + \Delta H[/tex]

We are also told from the reaction that

A few drops of the solution from test tube 1 added to a similar volume of the solution in test tube 3 produces carbon dioxide gas.

Generally  carbon dioxide gas  is produced is as a result of  a reaction between the acid HCl  and Na2CO3.

The reaction is

        [tex]2HCl -{(aq)} + Na_2 CO_3_{(aq)} \rightarrow 2 NaCl _{(aq)} + CO_2_{(g)} + H_2O_{(l)}[/tex]

Hence from this explanation above we see that the solution in test tube 1 is  0.10 M HCL while solution in test tube 2 is 0.10 M KOH and then solution in test tube three is  0.10 M Na2CO3

Which of the following elements has the largest atomic radius? Bromine, Barium, Magnsium, Zinc

Answers

Answer:

Atomic radii vary in a predictable way across the periodic table. As can be seen in the figures below, the atomic radius increases from top to bottom in a group, and decreases from left to right across a period. Thus, helium is the smallest element, and francium is the largest.

Explanation:

4. What reagent would you predict to be in excess for reacting 7.50 mL of a 0.10M BaCl2 solution with 7.50 mL of 0.10M KIO3 solution

Answers

Answer : [tex]BaCl_2[/tex] reagent predict to be in excess.

Explanation : Given,

Concentration of [tex]BaCl_2[/tex] = 0.10 M

Volume of [tex]BaCl_2[/tex] = 7.50 mL = 0.0075 L       (1 L = 1000 mL)

Concentration of [tex]KIO_3[/tex] = 0.10 M

Volume of [tex]KIO_3[/tex] = 7.50 mL = 0.0075 L

First we have to calculate the moles of [tex]BaCl_2[/tex]  and [tex]KIO_3[/tex].

[tex]\text{Moles of }BaCl_2=\text{Concentration of }BaCl_2\times \text{Volume of }BaCl_2[/tex]

[tex]\text{Moles of }BaCl_2=0.10M\times 0.0075L=0.00075mol[/tex]

and,

[tex]\text{Moles of }KIO_3=\text{Concentration of }KIO_3\times \text{Volume of }KIO_3[/tex]

[tex]\text{Moles of }KIO_3=0.10M\times 0.0075L=0.00075mol[/tex]

Now we have to calculate the excess and limiting reagent.

The balanced equilibrium reaction will be:

[tex]BaCl_2+2KIO_3\rightleftharpoons Ba(IO_3)_2+2KCl [/tex]

From the balanced reaction we conclude that

As, 2 mole of [tex]KIO_3[/tex] react with 1 mole of [tex]BaCl_2[/tex]

So, 0.00075 moles of [tex]KIO_3[/tex] react with [tex]\frac{0.00075}{2}=0.000375[/tex] moles of [tex]BaCl_2[/tex]

From this we conclude that, [tex]BaCl_2[/tex] is an excess reagent because the given moles are greater than the required moles and [tex]KIO_3[/tex] is a limiting reagent and it limits the formation of product.

Hence, [tex]BaCl_2[/tex] reagent predict to be in excess.

Rahul and Manav each were given a mixture of iron filings and sulphur powder. Rahul heated the mixture strongly and a new substance was formed. Write three points of difference between the two.Required to answer.​

Answers

Answer:

sure

Explanation:

The substance formed after heating the mixture of that of Rahul is caleed a compound. Whereas, Manav's mixture still remains in its current stae that is a heterogeneous mixture.

The compound formed is in black in color whereas the mixture is a mix of brownish-red and yellow.

The compound is a homogeneous mixture whereas the mixture is a heterogenous mixture because of its uneven distribution.

A piece of metal has a mass of 0.650 kilograms, has a width of 0.136 meters, and has a length of 0.0451 meters.Part A: If the metal’s volume is 291 cm3, what is the height of the metal in centimeters? (The width & length values given above are in a different unit!)

Part B: What is the density of this piece of metal?

Answers

Answer:

height = 4.74 cm

density = 2.23 g/ cm³

Explanation:

Mass of metal = 0.650 kg (650 g)

Width = 0.136 m    

Length = 0.0451 m  

Volume of metal = 291 cm³

Height in cm = ?

density of metal =?

Solution:

Width = 0.136 m    (0.136 m×100 cm/1m = 13.6 cm)

Length = 0.0451 m  (0.0451 m×100 cm/1m = 4.51 cm)

First of all we will calculate the height:

Volume = height× width× length

291 cm³ =      h     × 13.6 cm × 4.51 cm

291 cm³ =      h     × 61.34 cm²

h = 291 cm³ / 61.34 cm²

h = 4.74 cm

Density:

d = m/v

d = 650 g/291 cm³

d = 2.23 g/ cm³

In the laboratory you dissolve 18.7 g of copper(II) bromide in a volumetric flask and add water to a total volume of 375mL.

Required:
a. What is the molarity of the solution?
b. What is the concentration of the copper(II) cation?
c. What is the concentration of the acetate anion?

Answers

Answer:

a) - 0.2 M

b) - 0.2 M

c)- 0

Explanation:

The chemical formula of copper (II) bromide is CuBr₂. Its molar mass (MM) is calculated as follows:

MM(CuBr₂)= MM(Cu) + (2 x MM(Br) = 63.5 g/mol + (2 x 80 g/mol)= 223.5 g/mol

a). Molarity = moles CuBr₂/1 L solution

moles CuBr₂ = mass/MM = 18.7 g x 1 mol/223.5 g = 0.084 mol

Volume in L = 375 mL x 1 L/1000 mL = 0.375 L

M = 0.084 mol/(0.375 L) = 0.223 M ≅ 0.2 M

b). When is added to water, CuBr₂ dissociates into ions as follows:

CuBr₂ ⇒ Cu²⁺ + 2 Br⁻

We have 1 mol Cu²⁺ (copper (II) cation) per mol of CuBr₂. Thus, the concentration of copper (II) cation is:

0.2 mol CuBr₂ x 1 mol Cu²⁺/mol CuBr₂ = 0.2 M

c). The concentration of acetate anion is 0. There is no acetate anion in the solution (the anion from CuBr₂ is bromide Br⁻).

On the graph, which shows the potential energy curve of two N atoms, carefully sketch a curve that corresponds to the potential energy of two O atoms versus the distance between their nuclei.

Answers

Answer:

Explanation:

We are to carefully sketch a curve that relates to the potential energy of two O atoms versus the distance between their nuclei.

From the diagram, O2 have higher potential energy than the N2 molecule. Because on the periodic table, the atomic size increases from left to right on across the period, thus O2 posses a larger atomic size than N2 atom.

Therefore, the bond length formation between the two O atoms will be larger compared to that of the two N atoms.

which angles are right

Answers

Right angle acute angle obtuse angle

Answer:

a right is 90 degrees

How long would it take a bus traveling 52 km/h to travel 130 km

Answers

Answer:

2 and a half hours

Explanation:

Time is equal to distance over speed

When aqueous solutions of AgNO3 and KI are mixed, AgI precipitates. The balanced net ionic equation is ________. When aqueous solutions of AgNO3 and KI are mixed, AgI precipitates. The balanced net ionic equation is ________. AgNO3 (aq) + KI (aq) → AgI (s) + KNO3 (aq) Ag+ (aq) + I- (aq) → AgI (s) AgNO3 (aq) + KI (aq) → AgI (aq) + KNO3 (s) Ag+ (aq) + NO3 - (aq) → AgNO3 (aq) Ag+ (aq) + NO3 - (aq) → AgNO3 (s)

Answers

Answer:

Ag⁺ (aq) + I¯ (aq) —> AgI (s)

Explanation:

We'll begin by writing the dissociation equation for aqueous AgNO₃ and KI.

Aqueous AgNO₃ and KI will dissociate in solution as follow:

AgNO₃ (aq) —> Ag⁺(aq) + NO₃¯ (aq)

KI (aq) —> K⁺(aq) + I¯(aq)

Aqueous AgNO₃ and KI will react as follow:

AgNO₃ (aq) + KI (aq) —>

Ag⁺(aq) + NO₃¯ (aq) + K⁺ (aq) + I¯(aq) —> AgI (s) + K⁺ (aq) + NO₃¯ (aq)

Cancel out the spectator ions (i.e ions that appears on both sides of the equation) to obtain the net ionic equation. The spectator ions are K⁺ and NO₃¯.

Thus, the net ionic equation is:

Ag⁺ (aq) + I¯ (aq) —> AgI (s)

The net ionic equation of aqueous solutions of [tex]AgNO_3[/tex] and [tex]KI[/tex] to form [tex]AgI[/tex] precipitates is: B. [tex]Ag^{+}_{(aq)} + I^{-}_{(aq)}[/tex] -----> [tex]AgI_{(s)}[/tex]

A balanced chemical equation can be defined as a chemical equation wherein the number of atoms on the reactant (left) side is equal to the number of atoms on the product (right) side.

This ultimately implies that, both the charge on each atom and sum of the masses of the chemical compounds or elements in a chemical equation are properly balanced.

An ion can be defined as an atom or molecules (group of atoms) that has lost or gained one or more of its valence electrons, thereby, making it have a net positive or negative electrical charge.

First of all, we would write the dissociation equation for aqueous solutions of [tex]AgNO_3[/tex] and [tex]KI[/tex]:

For [tex]AgNO_3[/tex]:

[tex]AgNO_3_{(aq)}[/tex] -----> [tex]Ag^{+}_{(aq)} + NO_{3}^{-}_{(aq)}[/tex]

For [tex]KI[/tex]:

[tex]KI_{(aq)}[/tex] -----> [tex]K^{+}_{(aq)} + I^{-}_{(aq)}[/tex]

Next, we would write a chemical equation for the reaction of aqueous solutions of [tex]AgNO_3[/tex] and [tex]KI[/tex]:

[tex]AgNO_3_{(aq)} + KI_{(aq)}[/tex]  -----> [tex]Ag^{+}_{(aq)} + NO_{3}^{-}_{(aq)}[/tex] [tex]+ \;K^{+}_{(aq)} + I^{-}_{(aq)}[/tex] ----->[tex]AgI_{(s)} + K^{+}_{(aq)} + NO_{3}^{-}_{(aq)}[/tex]

Note: Spectator ions refers to the ions that exist as a reactant and a product in a chemical equation because they are unchanged by the chemical reaction.

In this chemical reaction, the spectator ions are:

[tex]K^+[/tex][tex]NO_{3}^{-}[/tex]

Finally, in order to obtain the net ionic equation, we would cancel out the two (2) spectator ions:

[tex]Ag^{+}_{(aq)} + I^{-}_{(aq)}[/tex] -----> [tex]AgI_{(s)}[/tex]

Read more: https://brainly.com/question/13750908

9 What 11 letter word describes the chemical balance within an organism?


___________________________________


10 What 7 letter word describes the waterproof outer layer for soft-bodies creatures?


___________________________________


11 What word starting with the letter "C" is the liquid material found within cells?


___________________________________


12 What word starting with the letter "C" is a process of organizing things into groups scientifically?


___________________________________

Answers

Answer:

9.) Homeostasis

10.) Epidermis

11.) Cytoplasim

12.) Classification

A bicycle rider is applying a force of 20 N while heading south against a wind blowing from the south with a force of 5 N

Answers

Answer:

the bike will go down 5 N

Which of the following best describes the structure of a nucleic acid?


a. Carbon ring(s)
b. Globular or fibrous
c. Single or double helix
d. Hydrocarbon(s)

Answers

It’s A. Carbon Rings

Gases A and B are confined to a cylinder and piston and react to form product C. As the reaction occurs, the system loses 1189 J of heat to surroundings. The piston moves downward as the gases react to form a solid. As the volume of the gas decreases under the constant pressure of the atmosphere, the surroundings do 311 J of work on the system. What is the change in the internal energy of the system

Answers

Answer:

The change in the internal energy of the system -878 J

Explanation:

Given;

energy lost by the system due to heat, Q = -1189 J (negative because energy was lost by the system)

Work done on the system, W = -311 J (negative because work was done on the system)

change in internal energy of the system, Δ U = ?

First law of thermodynamics states that the change in internal energy of a system (ΔU) equals the net heat transfer into the system (Q) minus the net work done by the system (W).

ΔU = Q - W

ΔU = -1189 - (-311)

ΔU = -1189 + 311

ΔU = -878 J

Therefore, the change in the internal energy of the system -878 J

If you collect 5.74 mL of O 2 at 298 K and 1.00 atm over 60.0 seconds from a reaction solution of 5.08 mL, what is the initial rate of the reaction

Answers

Answer:

7.71 × 10⁻⁴ M/s

Explanation:

The initial rate of the reaction can be expressed by using the formula:

[tex]\dfrac{\Delta [O_2]}{\Delta t}[/tex]

where the number of moles of O₂ = [tex]\dfrac{PV}{RT}[/tex]

where;

Pressue P = 1.00 atm

Volume V =5.74mL =  (5.74 /1000) L

Rate R = 0.082 L atm/mol.K

Temperature = 298 K

[tex]= \dfrac{1.00 \ atm \times \dfrac{5.74 }{1000}L}{0.082 \ L \ atm/mol.K \times 298 K}[/tex]

= 2.35 × 10⁻⁴ mol

Δ[O₂] = [tex]\dfrac{moles \ produced - initial \ mole}{\dfrac{5.08 }{1000}L }[/tex]

Δ[O₂] = [tex]\dfrac{2.35 \times 10^{-4} M - 0 M}{\dfrac{5.08 }{1000}}[/tex]

Δ[O₂]  = 0.04626 M

The initial rate = [tex]\dfrac{\Delta [O_2]}{\Delta t}[/tex]

= [tex]\dfrac{0.04626}{60}[/tex]

= 7.71 × 10⁻⁴ M/s

A geochemist has determined by measurements that there are moles of tin in a sample of cassiterite. How many moles of oxygen are in the sample

Answers

The question is incomplete, the complete question is:

This is the chemical formula for cassiterite (tin ore): SnO2 A geochemist has determined by measurements that there are 13. moles of tin in a sample of cassiterite. How many moles of oxygen are in the sample? Round your answer to 2 significant digits.

Answer:

Explanation:

In SnO2, there are two moles of oxygen for each mole of tin.

Hence, if there are 13 moles of tin, then we should have 13 * 2 moles of oxygen. This gives us 26 moles of oxygen.

Hence there are 26 moles of oxygen.

Which of the items below is a colloid?
a.fruit salad b.gelatin c.lacquer​

Answers

Answer:

b. gelatin

Explanation:

a homogeneous noncrystalline consisting of large molecules or ultramicroscopic particles of one substance.

The wood in my house is crumbling. *

Problem

Hypothesis

Law

Theory

Answers

Answer:

Problem

Explanation:

The given statement is a problem. It states the problem that the house of the speaker has been undergoing with. This problem gives rise to the Hypothesis in which the 'why' question is asked. The reason of the crumbling of the wood is stated in the hypothesis. Any reason placed of the happening of the event is stated to be hypothesis.

How many carbon atoms are in vitamin c?

Answers

Answer:

molecules can be much bigger. one molecule of vitamin c is made up of 20 atoms (6 carbons, 8 hydrogens, and 6 oxygens

3. How can the force of gravity affect weight?

Answers

Weight is a measure of how much gravity pulls on a mass or object. On the moon, there is less gravity pulling on objects, so they weigh less. ... Remember, even if you weigh less because of a change in gravity's force on your body, your body's mass is still the same.

What does the term mass mean in science?

A. The measure of the force of gravity on an object.

B. The amount of matter in an object.

C. The Amount of space that matter takes up.

Answers

The answer would be B. The scientific definition is the amount of matter in a substance or object

Answer:

B

Explanation:

Mass is defined as the quantity of matter in an object.

What is the mass in grams of 2.5 moles of Al?

Answers

Answer:

One mole of Al weighs 27g.

2.5 moles of Al weigh 67.5g.

what is the point of doing an experiment. Help thank you​

Answers

Answer:

to find out how somethings work

Explanation:

Answer:

Doing experiments is good because when you try these possibilities you can learn about something that you've tried or see why this experiment didn't really work. It also helps you understand that  not everything you try will work. that's why we experiment.

Explanation:

Hope this helps:)

what kind of bonds are there in H2O?​

Answers

Answer: it is covalent and there are 2 hydrogen molecules and 1 oxygen molecule.

Explanation: it just is

In H2O molecule, two water molecules are bonded by a Hydrogen bond but the bond between two H - O bonds within a water molecule are covalent.
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