Explanation:
An exothermic reaction is a "reaction for which the overall standard enthalpy change ΔH⚬ is negative." Exothermic reactions usually release heat and entail the replacement of weak bonds with stronger ones.
hope it helps
stay safe healthy and happy..Answer:
Exothermic reactions are reactions or processes that release energy, usually in the form of heat or light. In an exothermic reaction, energy is released because the total energy of the products is less than the total energy of the reactants.Explanation:
I hope this helps u have a nice day ☘Which of these is true about a pH meter?
It is inexpensive to use.
It measures pH indirectly.
It does not require calibration.
It can be used in any acid-base titration.
Answer:
That is, a pH meter is useful in detecting or knowing the acidity (due to ions) or alkalinity (due to ions) of a solution. Thus, we can conclude that out of the given options it is true about a pH meter that it can be used in any acid-base titration
Answer: D. It can be used in any acid-base titration.
Explanation:
If a shell can hold a maximum of 32 electrons, what is the value of n?
Answer:
The value of N would be 4.
Explanation:
The equation would be 2n^x = 32 and therefore, 4.
22)When iron rusts in air, iron(III) oxide is produced. How many moles of oxygen will react
with 2.4 mol of iron ?
4Fe(s) + 3O2(g) → 2Fe2O3(s)
A)1.2 mol
B)1.8 mol
C)2.4 mol
D)3.2 mol
E)4.8 mol
show work
Answer:
B
Explanation:
)When iron rusts in air, iron(III) oxide is produced. How many moles of oxygen will react
with 2.4 mol of iron ?
B)1.8 mol
Which list BEST identifies how the arrows should be arranged around the paper leaf in the model to represent the movement of matter and flow of energy during photosynthesis? A. Point into Leaf: sugars, oxygen (02), Point away from leaf: carbon dioxide(CO2), water(H2O) B. Point into Leaf: sugars, sunlight, Point away from leaf: carbon dioxide(CO2), oxygen (02), water(H2O) C. Point into Leaf: water(H2O), sunlight, Point away from leaf: carbon dioxide(CO2), sugars, oxygen (02) D. Point into Leaf: water(H2O), carbon dioxide(CO2) sunlight, Point away from leaf: sugars, oxygen (02
Answer:
D. Point into Leaf: water(H₂O), carbon dioxide (CO₂) sunlight, Point away from leaf: Sugars, oxygen (O₂)
Explanation:
Photosynthesis is the process used in the production of chemical energy in the form of energy containing organic compounds and oxygen from atmospheric carbon dioxide and liquid water enabled with the energy captured from light (mainly Sunlight) by the chlorophyll in green plants and other organisms
The basic chemical reaction involved in a photosynthesis reaction is presented as follows;
[tex]{}[/tex] Sunlight
[tex]{}[/tex] ↓
[tex]{}[/tex] CO₂ + H₂O (l) → C₆H₁₂O₆ + O₂
Carbon dioxide [tex]{}[/tex] Water Glucose Oxygen
Elias read a book about California earthquakes. He then wrote a three-
paragraph report about the book. Which of the following active reading
strategies did Elias use?
A. Making mental images
B. Drawing inferences
C. Summarizing
D. Making predictions
Which describes the forces in an unstable nucleus?
A. The electrostatic force is greater than the strong nuclear force.
B. The electrostatic force is greater than the weak nuclear force.
C. The weak nuclear force is greater than the strong nuclear force.
D. The strong nuclear force is greater than the electrostatic force.
Answer:
C. The weak nuclear force is greater than the strong nuclear force
copper +sulfur + oxygen =
What is the volume of 2.66 x 10^23 molecules of N2 gas at STP? PLEASE ANSWER WITH WORK! ILL GIVE BRAINLIEST
Answer:
1100L.
Explanation:
Which of these is not a mixture?
A) Salt
B) Cooking oil
C) Tea leaves
D) Milk
ty
Answer:
the answer is salt because it has a uniform and definite composition
Explanation:
Michael is studying the factors that affect corrosion of metals. He wants to test the effect that different concentrations of an acid will have on the corrosion of a metal. As he sets up and completes his experiment, which of the following experimental designs would be most likely to help him answer his question? A. Allow several metal samples to soak in different amounts of acid of a single concentration and then measure the amount of corrosion on each. B. Prepare solutions of different acid concentrations, measure 50 milliliters of each into different beakers, and place metal samples of different types but of the same mass into the beakers. C. After allowing several small metal sheets to be exposed to different acid concentrations, measure the surface area of each that is corroded. D. After allowing a small metal sheet to be exposed to one acid concentration, place it in different acid concentrations, then measure the surface area that is corroded.
Answer:
B. Prepare solutions of different acid concentrations, measure 50 milliliters of each into different beakers, and place metal samples of different types but of the same mass into the beakers.
Explanation:
Since Michael is studying the factors that affect corrosion of metals, and wants to test the effect that different concentrations of an acid will have on the corrosion of a metal, using different acid concentrations of the same volume on different metal samples of the same size would give a much better than all the other options because, a standard volume of acid is used and also a standard mass of metal is used. So, the effect can be measured quantitatively since we have the same quantity of sample.
So, option B is the answer
can someone explain the answer.
Answer:
A
Explanation:
Alkanes undergo substitution reaction with halogen molecules in the presence of light. This reaction occurs by free radical mechanism and the initiation step is the formation of the halogen radical.
The propagation steps involves the abstraction of a hydrogen from the alkane by the halogen radicals.
The termination steps involves the coupling of alky radicals.
Thus for the reaction of ethane and chlorine;
C2H6 + Cl2 -------> C2H5Cl + HCl
which two terms best describe the level of organization of life shown in this photo?
Answer:
there's no photo, I'm sorry
Describe the four states of matter.
You will not measure the enthalpy of the reaction of ______ in the coffee cup calorimeter because this reaction involves gases. Instead, you will use a well-known published value.
HCI and MgO
HCI and Mg
H2 and O2
Answer:
H2 and O2
Explanation:
A coffee cup calorimeter is basically a type of calorimeter that operates at constant pressure. The heat measured in the calorimeter is equal to the change in enthalpy of the reaction.
This type of calorimeter is apt for reactions involving solutions where there is little or no change in volume.
It is not generally applicable to gas phase reactions such as the reaction between H2 and O2.
Answer:
You will not measure the enthalpy of the reaction of
✔ H2 and O2
in the coffee cup calorimeter because this reaction involves gases. Instead, you will use a well-known published value.
C. H2 and O2
Is Correct
How much heat is required to raise the temperature of 16.0 grams H2O from 5.000C to 75.00C? Below is a list of constants.
specific heat for H2O(s) = 2.1 J/g0C
specific heat for H2O(L) = 4.18 J/g0C
specific heat for H2O(g) = 1.7 J/g0C
\bigtriangleup H△Hvap = 40.7 kJ/mol
\bigtriangleup H△Hfus = 6.01 kJ/mol
5.34 J
260 J
4680 J
2350 J
Answer:
The amount of heat required is 4681.6 J.
Explanation:
mass, m = 16 g = 0.016 kg
initial temperature, T = 5 C
final temperature, T' = 75 C
specific heat, c = 4.18 J/g C
The amount of heat required is
H = m c (T'- T)
H = 16 x 4.18 x (75 - 5)
H = 4681.6 J
Which equation represents the correct net ionic equation for the reaction between Ca(OH)2 and H2SO4?
Upper H superscript plus, plus upper O upper H superscript minus right arrow upper H subscript 2 upper O.
2 upper H superscript plus, plus 2 upper O upper H superscript minus right arrow upper H subscript 2 upper O.
Upper C a superscript 2 plus, plus 2 upper O upper H superscript minus, plus upper S upper O subscript 4 superscript 2 minus right arrow upper C a superscript 2 plus, plus upper S upper O subscript 4 superscript 2 minus, plus 2 upper H subscript 2 upper O.
Upper C a (upper O upper H) subscript 2 plus upper H subscript 2 upper S upper O subscript 4 right arrow upper C a upper S upper O subscript 4 plus 2 upper H subscript 2 upper O.
Answer: The correct net ionic equation for the reaction is [tex]2H^{+}(aq)+2OH^{-}(aq)\rightarrow 2H_2O(l)[/tex]
Explanation:
Net ionic equation is defined as the equations in which spectator ions are not included.
Spectator ions are the ones that are present equally on the reactant and product sides. They do not participate in the reaction.
The balanced molecular equation is:
[tex]Ca(OH)_2(aq)+H_2SO_4(aq)\rightarrow CaSO_4(aq)+2H_2O(l)[/tex]
The complete ionic equation follows:
[tex]Ca^{2+}(aq)+2OH^-(aq)+2H^+(aq)+SO_4^{2-}(aq)\rightarrow 2Ca^{2+}(aq)+SO_4^{2-}(aq)+H_2O(l)[/tex]
As calcium and sulfate ions are present on both sides of the reaction. Thus, they are considered spectator ions.
The net ionic equation follows:
[tex]2H^{+}(aq)+2OH^{-}(aq)\rightarrow 2H_2O(l)[/tex]
Hence, the correct net ionic equation for the reaction is [tex]2H^{+}(aq)+2OH^{-}(aq)\rightarrow 2H_2O(l)[/tex]
Answer:
B. no reaction
Explanation:
State three pieces of evidence from the diagram which indicate that the plant is pollinated by wind. ( 3 marks)
Your image is saying "Can't load image on this device."
What makes radioisotopes useful for dating objects?
O A. They have unique emission spectra.
O B. They decay at a predictable rate.
C. Their decay products are easy to detect.
O D. They all have extremely long half-lives.
Answer:A
Explanation:
Option D. They all have extremely long half-lives makes radioisotopes useful for dating objects.
What are radioisotopes?Radioisotopes exist as radioactive isotopes of an element. They can also be described as atoms that include an unstable combination of neutrons and protons, or surplus energy in their nucleus.
A radionuclide exists as a nuclide that contains excess nuclear energy, causing it unstable. This excess energy can be utilized in one of three methods: emitted from the nucleus as gamma radiation; assigned to one of its electrons to terminate it as a conversion electron; or utilized to create and emit a unique particle from the nucleus.
Radioactive isotopes of radium, thorium, and uranium, for example, exist found naturally in rocks and soil. Uranium and thorium also happen in trace amounts in water. Radon, induced by the radioactive decay of radium, stands present in the air.
Hence, Option D. They all have extremely long half-lives makes radioisotopes useful for dating objects.
To learn more about radioisotopes refer to:
https://brainly.com/question/18640165
#SPJ2
Calculate the total amount of energy required in calories to convert 50.0 g of ice at 0.00 degrees Celsius to steam at 100. degrees Celsius.
Specific heat capacity of water is 1.00 cal/g OC
Hfusion = 80 cal/g OC and Hvap = 540 cal/g OC
Write the complete equation you will use. 1 point
Substitute the values in the equation in step 1. 1 point
Report the math answer with 3 sig figs and the correct unit. 1 point
Answer:
HFusion*mass + Spec.Heat*mass*ΔT + HVap*mass
80cal/g*50.0g + 1.00cal/g°C*50.0g*(100°C-0°C) + 540cal/g*50g
3.60x10⁵cal
Explanation:
Using the HFusion we can find the heat needed to convert the ice to liquid water.
With specific heat capacity we can find the heat needed to increase the temperature of water from 0 to 100°C.
With HVap we can find the heat to convert the liquid water into steam.
The equations are:
HFusion*mass + Spec.Heat*mass*ΔT + HVap*massComputing the values:
80cal/g*50.0g + 1.00cal/g°C*50.0g*(100°C-0°C) + 540cal/g*50g36000cal =
3.60x10⁵calELECTRICITY IS ALLOWED TO PASS THROUGH ACIDIFIED WATER USING THE FOLLOWING EXPERIMENTAL SETUP.
QUESTION: IDENTIFY THE PROCESS
Answer: Electrolysis is passing an electric current through a liquid containing ions so that decomposition reaction takes place.
Electrolysis is passing an electric current through a liquid containing ions so that decomposition reaction takes place.When an electric current is passed through acidified water, it decomposes to give hydrogen and oxygen gas. The hydrogen gas is obtained at the cathode and the oxygen gas is obtained at the anode.
Electrolysis is passing an electric current through a liquid containing ions so that decomposition reaction takes place.When an electric current is passed through acidified water, it decomposes to give hydrogen and oxygen gas. The hydrogen gas is obtained at the cathode and the oxygen gas is obtained at the anode.The reaction for decomposition of water into oxygen and hydrogen is as follows:
Electrolysis is passing an electric current through a liquid containing ions so that decomposition reaction takes place.When an electric current is passed through acidified water, it decomposes to give hydrogen and oxygen gas. The hydrogen gas is obtained at the cathode and the oxygen gas is obtained at the anode.The reaction for decomposition of water into oxygen and hydrogen is as follows:2H2O(l) -------> 2H2(g) + O2(g)
What is a balanced nuclear equation for the alpha decay of Strontium-90?
Answer: The balanced nuclear equation for the alpha decay of Sr-90 is [tex]_{38}^{90}\textrm{Sr}\rightarrow _{36}^{86}\textrm{Kr}+_2^4\alpha[/tex]
Explanation:
A nuclear reaction is defined as the reaction in which the changes in the nucleus of an atom take place and usually form a different element. The types of decay processes are:
Alpha decayBeta-decayGamma decayAlpha decay is the process in which a heavy nucleus decays into a light nucleus with the release of an alpha particle. This alpha particle carries a charge of +2 units and has a mass of 4 units. It is also known as the helium nucleus. The general equation for this decay process is:
[tex]X_Z^A\rightarrow Y_{Z-2}^{A-4}+\alpha _2^4[/tex]
The nuclear equation for the alpha decay of strontium-90 isotope follows:
[tex]_{38}^{90}\textrm{Sr}\rightarrow _{36}^{86}\textrm{Kr}+_2^4\alpha[/tex]
Barbara is conducting an experiment to observe heat flow. She places one piece of metal in a freezer at -18 degrees Celsius (°C) and a second piece of metal in an oven at 200 °C. After 2 hours, she takes the metal pieces out of the freezer and oven and places them both in the same beaker of boiling water for two minutes. Which of the following best describes how some of the heat will initially move in this system?
Heat will flow from the frozen metal into the hot metal.
Heat will flow from the boiling water into the hot metal.
Heat will flow from the boiling water into the frozen metal.
Heat will flow from the frozen metal into the boiling water.
Answer: The correct answer is heat will flow from the boiling water into the frozen metal.
Explanation:
According to the law of conservation of energy, energy cannot be destroyed nor created but it can be transformed from 1 form to another form.
There are 3 processes of heat transfer:
Conduction: This type of heat transfer occurs when there is direct contact between the two objects.Convection: This type of heat transfer occurs when there is a movement of fluid (liquid or gas) due to the movement of hot layers to the top and cold layers to the bottom which leads to convection currents. Radiation: This type of heat transfer occurs when there is a direct transfer of energy through space.The heat moves from a hot surface to a cold surface to maintain equilibrium.
We are given:
A metal is placed in a freezer (cold object) and another metal is placed in an oven (hot object) and then both the metals are placed in boiling water.
Initially, the heat will flow from the boiling water (hot object) into the frozen metal (cold object) to maintain equilibrium
Hence, the correct answer is heat will flow from the boiling water into the frozen metal.
Given 7 moles of nitrogen gas, how many moles of ammonia can you make?
Explanation:
just use the molar ratios to figure it out. Notice, you have to balance the chemical equation.
water is to ____as liquid is to soild
water is to gas as liquid is to solid
7. A sample of methane gas (CH.) with a mass of 58 g is kept in a 1500 mL container at a temperature of 100. °C. What is the pressure of the gas?
Answer:
c i took the text
Explanation:
an atom of an element is represented as 39/19x, write its
(1) number of protons
(2)number of neutrons
(3)Electric configuration
(4)number of valence electrons
Answer:
Solution :
Lithium
Z = 3
P = 3
E = 3 = (2, 1) p=3
A = 7 n=4
P + n = A
3 + n = 7
N = 4

Carbon
Z = 6
P = 6
E = 6 = (2, 4) p=6
A = 12 n=6
P + n = A
6 + n = 12
N = 6
The strength of the gravitational attraction depends on the mass of the objects involved and the distance between them. The gravitational force between two objects will be lowest in which of the following situations?
A. Both objects have small masses and are close together.
B. One object has a large mass, and the objects are close together.
C. Both objects have large masses and are close together.
D. Both objects have small masses and are far apart.
Answer:
d sguro
Explanation:
I'm not sure kung ayan ba
Help me with this this is something i dont know and its not on here please help meeeeeee
Answer:
it would be option A
Explanation:
This is becuase if you look at the chart you can see tyhat the group of rats that got feed to vitamans did gain more wati then the ones on the normal diet.
Matter takes up _____.
(a) Space and temperature
(b) Space and heat
(c) Space and mass
(d) Heat and temperature
PLZ HELP!!! What mass of [tex]SrF_{2}[/tex] can be prepared from the reaction of 10.0g [tex]Sr(OH)_{2}[/tex] with excess HF? THANK U!!
Answer:
Approximately 10.5g or 10.4g [tex]SrF_{2}[/tex]
