Using salt and ice to make ice cream is an example of:

Answers

Answer 1

Answer:

An exothermic reaction

Explanation:


Related Questions

The acid dissociation constant, Ka, of HSO4- is 1.2 × 10-2. What does the Ka value indicate about this compound?
A.
HSO4- is a weak base.
B.
HSO4- is a strong acid.
C.
HSO4- is a weak acid.
D.
HSO4- is a strong base.

Answers

Answer:

The answer is HSO4- is a weak acid which will be C

The acid dissociation constant, ka, of HSO4- indicates that it is a strong acid. Details about acid dissociation constant can be found below.

What is acid dissociation constant?

The acid dissociation constant denoted by Ka is the measure of the strength of an acid.

The dissociation constant of an acid is used to identify strong acids from their weak counterparts. Strong acids have high Ka values while weak acids have low Ka values.

According to this question, the Ka of HSO4- is 1.2 × 10-², which is quite high.

Therefore, the dissociation constant, ka, of HSO4- suggests that it is a strong acid.

Learn more about acid dissociation constant at: https://brainly.com/question/4363472

#SPJ9

Rank these solutions from the most alkaline (1) to the least alkaline (5).

Answers

I think the answers are 45 and 60

How long does it take, on average, for one centimetre of soil to form

Answers

The time needed to form a soil depends on the latitude: in environments characterized by a mild climate, it takes 200-400 years to form 1 cm of soil. in wet tropical areas soil formation is faster, as it takes 200 years. in order to accumulate enough substances to make a soil fertile it takes 3000 years.

what is the atomicity of Sulphur?​

Answers

Answer:

the atomicity of sulphur is 8

Explanation:

hope it helps

Had beryllium and calcium already been discovered

Answers

Answer:

Yes

Beryllium is a chemical element with the symbol Be and atomic number 4. It is a steel-gray, strong, lightweight and brittle alkaline earth metal. ... Notable gemstones high in beryllium include beryl (aquamarine, emerald) and chrysoberyl.

Calcium is a mineral that is necessary for life. In addition to building bones and keeping them healthy, calcium enables our blood to clot, our muscles to contract, and our heart to beat. About 99% of the calcium in our bodies is in our bones and teeth.

Write the empirical formula for the hydrated KAl(SO4)2, based on your experimental results and answer to Question 2. Show all work including units.
Hint: if the ratio of moles of H2O to moles of anhydrous KAl(SO4)2 was 4, then the empirical formula would be: KAl(SO4)2•4H2O.

Answer to Question 2:
Ratio of 2:3

Answers

Answer:

Therefore mole ratio is [tex]H_{2}O[/tex] : [tex]KAl(SO_{4} )_{2}[/tex] is 12 :1  

Empirical formula is [tex]KAl(SO_{4} )_{2}. 12 H_{2}O[/tex].

Explanation:

The chemical formula of a hydrate  

Moles of anhydrous [tex]KAl(SO_{4} )_{2}[/tex]  

Molar mass of [tex]KAl(SO_{4} )_{2}[/tex] = 258.21 g /mol  

Mass of anhydrous [tex]KAl(SO_{4} )_{2}[/tex] = [mass of aluminum cup + alum after 2nd heating] –[ mass of empty cup]  

                                                   = 3.5 g – 2.4 g  

                                                   = 1.1 g

Moles of [tex]KAl(SO_{4} )_{2}[/tex]= mass / molar mass  

                                    = 1.1 g / 258.21 g per mol  

                                   = 0.00426 mol [tex]KAl(SO_{4} )_{2}[/tex]

The mole ratio of the H2O to [tex]KAl(SO_{4} )_{2}[/tex]

Mole ratio = moles of H2O/ moles of [tex]KAl(SO_{4} )_{2}[/tex]

                  = 0.05 mol H2O / 0.00462 mol [tex]KAl(SO_{4} )_{2}[/tex]

                 = 11.7

We can round the 11.7 to closest whole number = 12

Therefore mole ratio is [tex]H_{2}O[/tex] : [tex]KAl(SO_{4} )_{2}[/tex] is 12 :1  

Empirical formula = [tex]KAl(SO_{4} )_{2}. 12 H_{2}O[/tex]  

So we have 12 moles of water as the water of hydration in the empirical formula.  

Alum hydrate is that the white crystalline solid after heating it'll start melting due to the water of hydration present in it then again solid will remain within the aluminum cup once all the water is given off within the sort of vapors.  

b) if the scholar used 2.20 g of the sample but within the calculation, he started with 2.0 g sample then  

when the mass of water is calculated using this data the mass of water is going to be higher therefore it gives more moles of water within the hydrate.  

So the final answer is going to be artificially high.

please help me with this

Answers

Answer:

a. B

b. C

c. A

d. A

e. B

f. -266

g. B and D

Now look at the volcano map what type of boundary tends to give rise to volcanic activity

Answers

divergent and convergent plate boundaries cause volcanic activity

Answer:

Volcanoes occur primarily on convergent boundaries, specifically oceanic-continental convergent boundaries.

Explanation:

plato

Explain the steps you would follow to make 500 mL of a 0.3 M solution of sucrose
(C12H22011) in the lab.

Answers

Answer:

see explanation

Explanation:

Solutions are prepared from one of three solute sources ...

- solid solute from manufacturer,

-liquid solute from manufacturer,

-stock concentrate of solute for dilution to lower concentrations.

In this problem, sucrose is a stock solid with a formula mass of 342.3 grams/mol. The amount of solid needed can be determined using the formula:

mass of solute needed (grams) = (Molarity needed x Volume needed in Liters x formula weight) / (decimal fraction purity of stock solid)

Molarity needed = 0.3M

Volume needed = 500 ml = 0.500 liters

Formula weight = 342.3 grams/mole

Purity factor (assumed) = 100% = 1.00 (should be posted on stock bottle label) For example, a 95% pure stock solid => purity factor of 0.95.

∴ grams of sucrose needed = (0.3M*)(0.500L)(342.3g/mole)/(1.00) =51.345 grams sucrose.

Measure 51.345 grams of sucrose into mixing vessel and add solvent water up to, but not to exceed 500 ml total volume. Mix until homogeneous.

H2S04+CaCO3—>Ca S04+H20 +CO 2


help me balance it​

Answers

Answer:

It's already balanced.

Explanation:

REACTANTS PRODUCTS

H = 2 H =2

S = 1 S = 1

O = 7 O = 7

Ca = 1 Ca = 1

C = 1 C =1

Consider the half reactions below for a chemical reaction.
ZnZn2+ (aq) + 2e
Cu?" (aq) + 2e → Cu(s)
What is the overall equation for this chemical reaction?
Zn(s)+ Cu?* (aq) —>Zn2+ (aq) + Cu(s)
O Zn(s) + Cu2+ (aq) — Cu2+ (aq) + 2e-
O Zn2*(aq) + Cu(s) —> Cu2* (aq) + Zn(s)
O Zn2+ (aq) + 22 —> Cu2(aq) + 2e

Answers

Answer:

Option A:

Zn(s) + Cu^(2+) (aq) → Cu(s) + Zn^(2+)(aq)

Explanation:

The half reactions given are:

Zn(s) → Zn^(2+)(aq) + 2e^(-)

Cu^(2+) (aq) + 2e^(-) → Cu(s)

From the given half reactions, we can see that in the first one, Zn undergoes oxidation to produce Zn^(2+).

While in the second half reaction, Cu^(2+) is reduced to Cu.

Thus, for the overall reaction, we will add both half reactions to get;

Zn(s) + Cu^(2+) (aq) + 2e^(-) → Cu(s) + Zn^(2+)(aq) + 2e^(-)

2e^(-) will cancel out to give us;

Zn(s) + Cu^(2+) (aq) → Cu(s) + Zn^(2+)(aq)

phosphorus react with carbon

Answers

Answer:

Phosphorus atoms can bond with oxygen atoms to form ester groups. These can bond with carbon atoms, yielding a large number of organic phosphorus chemicals. These are found in many important biological processes


A gas has an initial volume of 52.3 L at 273 Kelvin. What is its temperature when the volume reaches 145.7 L?

Answers

Answer:

[tex]\boxed {\boxed {\sf 761 \ K}}[/tex]

Explanation:

We are asked to find the new temperature of a gas after a change in volume. We will use Charles's Law, which states the volume of a gas is directly proportional to the temperature. The formula for this law is:

[tex]\frac {V_1}{T_1}= \frac{V_2}{T_2}[/tex]

The volume is initially 52.3 liters at a temperature of 273 Kelvin.

[tex]\frac {52.3 \ L}{273 \ K}= \frac{V_2}{T_2}[/tex]

The volume reaches 145.7 liters at an unknown temperature.

[tex]\frac {52.3 \ L}{273 \ K}= \frac{145.7 \ L }{T_2}[/tex]

We are solving for the new temperature, so we must isolate the variable T₂.  Cross multiply. Multiply the first numerator and second denominator, then the first denominator and second numerator.

[tex]52.3 \ L * T_2 = 273 \ K * 145.7 \ L[/tex]

Now the variable is being multiplied by 52.3 liters. The inverse of multiplication is division. Divide both sides by 52.3 L.

[tex]\frac {52.3 \ L * T_2 }{52.3 \ L}=\frac{ 273 \ K * 145.7 \ L}{52.3 \ L}[/tex]

[tex]T_2=\frac{ 273 \ K * 145.7 \ L}{52.3 \ L}[/tex]

The units of liters cancel.

[tex]T_2=\frac{ 273 \ K * 145.7 }{52.3 }[/tex]

[tex]T_2 = 760.5372849 \ K[/tex]

The original measurements have at least 3 significant figures, so our answer must have 3. For the number we found, that is the ones place. The 5 in the tenths place tells us to round the 0 up to a 1.

[tex]T_2 \approx 761 \ K[/tex]

When the volume reaches 145.7 liters, the temperature is 761 Kelvin.

ii.
ci
What is the name of the organic compound

Answers

hydroxyl, carboxyl, amino, methyl and phosphate groups

Answer.

Hydrocarbons are compounds that contain carbon and hydrogen only

Explanation:

a. c3H4 methane

b.c3H4.propene

c.c5H8

write electronic configuration of chlorine in its ionic state?​

Answers

Answer:

1s2 2s2 2p6 3s2 3p6

Explanation:

Chlorine is a groups 17 element. The halogens for ions by accepting one electron to form univalent negative ions.

Since chlorine normally contains seventeen electrons, the chloride ion consists of eighteen electrons.

Hence the electronic configuration of chlorine ion is; 1s2 2s2 2p6 3s2 3p6.

hii pls help me to balance chemical equation

calcium hydroxide + hydrochloric acid ------> calcium chloride + water​

Answers

Answer:

1 Ca(OH)2 + 2 HCl ---> 1 CaCl2 + 2 H2O

Determine which elements or compounds are products in the
follow reaction equation:

Answers

Answer: D is the answer since it is the product of this equation

Explanation: HOPE I AM RIGHT AND IT HELPS!!!

need more explanation feel free to comment in the comment box

A 2.50 L container is filled with 175 g of argon; a. If the pressure is 10 atm, what is the temperature ? b if the temperature is 22K, what is the pressure ?

Answers

Answer:

A. 70 K

B. 3.16 atm

Explanation:

We'll begin by calculating the number of mole in 175 g of Ar. This can be obtained as follow:

Mass of Ar = 175 g

Molar mass of Ar = 40 g/mol

Mole of Ar =?

Mole = mass / molar mass

Mole of Ar = 175 / 40

Mole of Ar = 4.375 moles

A. Determination of the temperature.

Mole of Ar (n) = 4.375 moles

Volume (V) = 2.50 L

Pressure (P) = 10 atm

Gas constant (R) = 0.0821 atm.L/Kmol

Temperature (T) =?

PV = nRT

10 × 2.5 = 4.375 × 0.0821 × T

25 = 4.375 × 0.0821 × T

Divide both side by (4.375 × 0.0821)

T = 25 / (4.375 × 0.0821)

T ≈ 70 K

B. Determination of the pressure.

Mole of Ar (n) = 4.375 moles

Volume (V) = 2.50 L

Temperature (T) = 22 K

Gas constant (R) = 0.0821 atm.L/Kmol

Pressure (P) =?

PV = nRT

P × 2.5 = 4.375 × 0.0821 × 22

Divide both side by 2.5

P = (4.375 × 0.0821 × 22) / 2.5

P = 3.16 atm.

balance the equation .......qn 5.......help​

Answers

Answer:

MnO4 + 4 H2C2O4 = Mn + 8 CO2 + 4 H2O

Which of the following are true for an element?       (i)Atomic number= number of protons + number of electrons      (ii)Mass number = number of protons+ number of neutrons      (iii)Atomic mass= number of protons= number of neutrons      (iv)Atomic number = number of protons = number of electrons​

Answers

Answer:

ii and iv

Explanation:

atomic mass is the sum of protons and neutrons

protons ( postively charged) usually have the same number like electrons( negatively charged)

¿Que es bacteria y un virus ?
es para hoy por favor ayúdeme

Answers

i) Las bacterias son organismos microscópicos unicelulares que prosperan en diversos entornos. Estos organismos pueden vivir en el suelo, el océano y dentro del intestino humano.

ii) Un virus es un agente infeccioso submicroscópico que se replica solo dentro de las células vivas de un organismo. Los virus infectan todas las formas de vida, desde animales y plantas hasta microorganismos, incluidas bacterias y arqueas.

Los antibióticos solo son necesarios para tratar ciertas infecciones causadas por bacterias. Las enfermedades virales no pueden tratarse con antibióticos. Cuando tomar antibióticos no sea lo indicado, pídale a su profesional de atención médica consejos sobre cómo aliviar los síntomas y sentirse mejor.
Enfermedad común
Causa común
¿Se necesitan antibióticos?
Bacteria
Bacteria o virus
Virus
Infección estreptocócica de la garganta (strep)

Tosferina

Infección de las vías urinarias

Sinusitis
Tal vez
Infección del oído medio
Tal vez
Bronquitis/resfriado con congestión de pecho (en niños y adultos)*
No*
Resfriado común/moqueo
No
Dolor de garganta (excepto por infección estreptocócica)
No
Influenza (gripe)
No

Which letter in the diagram represents the transition from liquid to gas?
A
B
C
D

Answers

Answer:

D

Explanation:

B is solid and liquid while D is liquid and gas

Answer:

Option ( D) is correct

The phase transition occurs at 100o C (the normal boiling point of water). Liquid water becomes water vapor or steam when it enters the gaseous phase.

Explanation:

A heating curve graphically represents the phase transitions that a substance undergoes as heat is added to it.

The liquid will begin to boil when enough heat has been absorbed by the solution that the temperature reaches the boiling point, where again, the temperature remains constant until all of the liquid has become gaseous water. At the atmospheric pressure of 1 atm, this phase transition occurs at 100o C (the normal boiling point of water). Liquid water becomes water vapor or steam when it enters the gaseous phase. Use the heat of vaporization ([latex]\Delta H_{vap}[/latex] ) to calculate how much heat was absorbed in this process: [latex]q=m\cdot C_{H_2O(g)}\cdot \Delta T[/latex], where m is the mass of the sample of water.

After all of the liquid has been converted to gas, the temperature will continue to increase as heat as added. Again, the heat added that results in a certain change temperature is given by: [latex]q=m\cdot C_{H_2O(g)}\cdot \Delta T[/latex] . Note that the specific heat capacity of gaseous water is different than that of ice or liquid water.

Pls help!!!
You are given a type of element by a teacher and she asks you to identify it.What should you do?Explain your answer​

Answers

Answer:

NAO SRESONDEPORR PQUEOU BUOBRRRA  IGAD THCAAUSEI

Explanation:

Draw the structure for :

3,3,4-trimethylhex-2-ene

Answers

Answer:

answer is in the picture.

Help me please

The options are
A. Translation
B. Rotation
C. Enlargement
D.reduction

Answers

this is enlargement since the new image has been enlarged twice the size of the original.

translation means it has moved
rotation means it turned another way
reduction means it got smaller

Answer:

C. Enlargement

Explanation:

Which of the following elements would have the largest electronegativity value?
O cesium
Olithium
O carbon
O sodium

Answers

I’m going to go with lithium

What is an air mass? Where on Earth might you find a hot and dry air mass?

Answers

An air mass is a large volume of air in the atmosphere thats mostly uniform in temperature and moisture. Air masses can extend thousands of kilometers across the surface of the Earth, and can reach from ground level to the stratosphere/10 miles into the atmosphere. an air mass over northern Canada is a continental polar air mass and is cold and dry. One that forms over the Indian Ocean is called a maritime tropical air mass and is warm and humid.

An air mass is a volume of air whose temperature and humidity are specified. Many hundreds or thousands of square miles are covered by air masses, which adjust to the properties of the land underneath them.

What is an air mass ?

An air mass is a volume of air whose temperature and humidity are specified. Many hundreds or thousands of square miles are covered by air masses, which adjust to the properties of the land underneath them. Latitude and their continental or marine source regions are used to categorize them.

There is a temperature and air pressure differential. Storms are caused by abrupt changes in the weather. Two natural wind patterns come into conflict.

The hot and dry continental tropical (cT) air mass is prevalent over subtropical and tropical continents. The world's largest deserts, such the Sahara, Arabian, and Australian, are important source areas.

Thus, Latitude and their continental or marine source regions are used to categorize them. An air mass is a volume of air whose temperature and humidity are specified.

To learn more about an air mass, follow the link;

https://brainly.com/question/28709357

#SPJ2

mendeleev's periodic table is studied even though it is considered to be defective​

Answers

Answer:

This is because Mendeleev arranged the elements in order of increasing relative atomic mass.

Explanation:

Dmitri Mendeleev is one of the scientists that contributed to the development of periodic table in chemistry. He was able to organise elements into rows according to their atomic mass and into columns based on chemical and physical properties. This is the main reason why his periodic table is still studied even though it has some defects which include:

--> Grouping of elements that are not similar chemically: For example Copper and Silver bear no resemblance with the alkali metals, but they have been placed together in the first group.

--> Position of isotopes: According to his periodic table: Isotopes of an element must be given separate places in the periodic table because they have different atomic masses.

--> Electronic arrangement of elements: It failed to explain the electronic arrangement of elements.

--> Separation of chemically similar elements:

Elements that are chemically similar such as Gold and Platinum have been placed in separate groups.

Which of the following is an oxide which is strongly acidic?
(a) Na2O.
(b) MgO
(c) SiO2.
(d) P2O5.

Answers

Answer:

answer of your question is 4th

Explanation:

P205

How many moles of electrons is required to deposit 5.6g of iron from a solution of iron (2) tetraoxosulphate(6)

Answers

Answer:

0.20 mol

Explanation:

Let's consider the reduction of iron from an aqueous solution of iron (II).

Fe²⁺ + 2 e⁻ ⇒ Fe

The molar mass of Fe is 55.85 g/mol. The moles corresponding to 5.6 g of Fe are:

5.6 g × 1 mol/55.85 g = 0.10 mol

2 moles of electrons are required to deposit 1 mole of Fe. The moles of electrons required to deposit 0.10 moles of Fe are

0.10 mol Fe × 2 mol e⁻/1 mol Fe = 0.20 mol e⁻

0.20 mol of electrons is required to deposit 5.6g of iron from a solution of iron (2) tetraoxosulphate(6)

 The reduction of iron from an aqueous solution of iron (II).

[tex]Fe^{+2} +2e^{-} \rightarrow Fe[/tex]

The formula for number of moles is as follows:-

[tex]Number \ of \ moles=\frac{Mass}{Molar\ mass}[/tex]

The molar mass of Fe is 55.85 g/mol. The moles corresponding to 5.6 g of Fe are:

[tex]5.6 g \times\frac{1\ mol}{55.85\ g} = 0.10 \ mol[/tex]

2 moles of electrons are required to deposit 1 mole of Fe. The moles of electrons required to deposit 0.10 moles of Fe are:-

[tex]0.10 mol Fe\times\frac{2\ mol\ e^{-} }{1\ mol\ e^{-}} = 0.20 \ mol e^{-}[/tex]

Hence, 0.20 mol of electrons is required to deposit 5.6g of iron.

To know more about:-

brainly.com/question/12513822

Other Questions
What Is Digestive system ? Find the value of the constant m 150 - 12m + 54 = 0 Qu paises durante el estado moderno desarrollaron la Monarqua Parlamentaria? Which phrase is an example of effective speaking in a classroom discussion?I cant believe you feel that way! Listen to me, Ill change your mind.Wow! Where did you find that unbelievable information?In my personal opinion, the only way to answer the question is . . .I can understand your feelings, but my research shows that . . . 10 pipes can fill a tank in 16 minutes,in how many minutes would 8 pipes fill the same tank ,proportion question a shopkeeper gains #1.75 by selling an article for #6.25. what is the percentage gain. Suppose ABCD's stock price is currently $50. In the next six months, it will either fall to $40 or rise 8 to $60. What is the current value of a six-month call option with an exercise price of $50? The six- month risk-free interest rate is 2% (periodic rate). A. $5.39 B. $15.00 C. $8.25 D. $8.09 If music be the food of love, play on. What does the phrase 'dying fall' most likely mean in both excertp? At the city museum, child admission is and adult admission is . On Wednesday, three times as many adult tickets as child tickets were sold, for a total sales of . How many child tickets were sold that day Can u help solve this problem Pls help me with this question ASAP how does growth of a business affect exports Mr jones rolls a 6 sided cube mumbered 1,2,3,4,5,6, what is the probability he rolls a three. a new automobile cause 11300 which is 100 more than 25 times a certain number what is the number Parents should protect their children's mental health by limiting how much they use social media. For problems 1 - 4, identify whether each figure is a point, line, or line segment. Then write its name. Please help! Was due yesterday! 999999999999999*22222222222222 William asked to his coffee to be brought to the conference room A traveling salesman figures it costs 28cents for every mile he drives his car. How much does it cost him (in dollars) a week to drive his car if he travels 315 miles a week? Find the Length of the missing side of the right Triangle using the Pythagorean Theorem. Round your answers tothe nearest tenth. Please show your work in the "Show your work" text box. Draw a Picture!The size of a television screen is given by the length of the diagonal ofthe screen. What size is a television screen that is 21.6 inches wide and16.2 inches high?Show Your WorkO 22.5 in18.4 in27 inO 13.2 in