Answer:C
Explanation:
Got it right in usatestprep
The physical evidence that indicates that there has been a chemical reaction is that the beaker changes temperature and the correct option is option C.
What is Neutralization reaction?
Neutralization is a chemical reaction in which acid and base react to form salt and water. Hydrogen (H⁺) ions and hydroxide (OH⁻ ions) react with each other to form water.
The strong acid and strong base neutralization have a pH value of 7.
The beaker gets warm which indicates that the reaction between acid and base is an exothermic reaction releasing heat energy into the surroundings.
Therefore, The physical evidence that indicates that there has been a chemical reaction is that the beaker changes temperature and the correct option is option C.
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I need help with the first question, if you can help with the other two I would really appreciate it!
Answer:
5
Explanation:
Which statement most accurately describes a chemical equation?
a. in a chemical reaction, the mass of the energy change must be equal to the energy used
b. in a chemical reaction, the mass of the products must equal the mass of the reactants
c. in a chemical reaction, the mass of each product must be the same
d. in a chemical reaction, the combined mass of the container the substances is always equal
Answer: A
Explanation:
TEACH ME how to do question 2 through your explanations.
Answer:
Explanation:
The first two are easy:
H2O, H3O+ and OH- all exist in an equilibrium
[H3O+] = [OH-] = 10^-7 M
HCl is a strong acid so 1M of it will disassociate completely
[H3O+] = [Cl-] = 1 M
The third one is also an equilibrium as HNO2 is a weak acid. Ka is given so [HNO2] and [NO2-] can be calculated.
The fourth one is a buffer solution so its pH can be looked up to give the concentrations.
Answer:
Explanation:
H20 has pH of 7
1st reaction [H30+] = 10^-7M
[OH-] = 10^-7M
1M HCl has pH of 0
2nd reaction [H3O+] = 1M
[Cl-] = 1M
given Ka = 4.6x10^-3 = [H3O+]x[NO2-] / [HNO2]
and [HNO2] + [NO2-] = 1M
each concentration can be solved
beaker D is a buffer solution n requires more info 2 solve
Which part of the scientific process is a proposed answer to a question?
1. observation
2. experiment
3. hypothesis
4. results
Scientific processes are the steps that are done to research and draw conclusions. The results of the experiments are the proposed answer to a question. Thus, option 4 is correct.
What are the steps of the scientific process?The scientific process initiates when there is a question that needs to answer and presented with observations and facts. It includes defining the question and making observations.
From the observations, the hypothesis is formed and an experiment is designed and conducted. From the research, the conclusion and the results are drawn.
Therefore, option 4. the proposed answer is called the result.
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Answer:
Hypothesis
Explanation:
Hypothesis is an educated guess as to what the answer to the question is.
(*) Sorry for my late answer but I hope this helps others that are looking for this.
I got 100% ;)
2COOH
How many of each element is present in the following formula?
Is everything correct?
Older stars get smaller and cooler and are called white dwarfs.
True
Answer:
si
Explanation:
trye
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kaisksd
Al hacer reaccionar 5g de cinc con ácido sulfúrico se observa que la reacción ocurre en 20s. ¿Cuál será la rapidez de la reacción? Masa atómica del cinc 65,37g.
Answer:
0.0038 mole s-1
Explanation:
La velocidad de una reacción se refiere a la rapidez o la lentitud con que avanza una reacción. Se mide por la cantidad de reactivos que desaparecen por unidad de tiempo o por la cantidad de productos que aparecen por unidad de tiempo.
Número de moles de zinc = 5g / 65.37gmol-1 = 0.076 moles
Velocidad de reacción = 0.076 moles - 0 moles / 20 s - 0s = 0.0038 mole s-1
Balance the Chemical Equation. Fill in the Missing Coefficients. GeF3 + Cs = CsF + Ge
what is the chemical formula for sugar ( in water)?
Magnesium (used in the manufacture of light alloys) reacts with iron(III) chloride to form magnesium chloride and iron. A mixture of 41.0 g of magnesium and 175.0 g of iron(III) chloride is allowed to react. Identify the limiting reactant and determine the mass of the excess reactant present in the vessel when the reaction is complete. Select one: a. Limiting reactant is Mg; 7.4 g of FeCl3 remain. b. Limiting reactant is Mg; 46.5 g of FeCl3 remain. c. Limiting reactant is FeCl3; 1.7 g of Mg remain. d. Limiting reactant is FeCl3; 37.8 g of Mg remain. e. Limiting reactant is Mg; 134.0 g of FeCl3 remain.
Answer:
Limiting reactant is FeCl3; 1.7 g of Mg remain.
Explanation:
From the question;
The equation is;
3Mg(s) + 2FeCl₃(s) → 3MgCl₂(s) + 2Fe(s)
Amount of Mg = 41 g/24.31 g/mol = 1.687 moles
The limiting reactant yields the least amount of MgCl2
3 moles of Mg yields 3 moles of MgCl2
Hence 1.687 moles of Mg yields yields 1.687 moles of MgCl2
FeCl₃ = 175 g/162.2 g/mol = 1.0789 moles
2 moles of FeCl3 yields 3 moles of MgCl2
1.0789 moles of FeCl3 yields 1.0789 * 3/2 = 1.61835 moles of MgCl2
Hence FeCl3 is the limiting reactant
3 moles of Mg reacts with 2 moles of FeCl3
x moles of Mg reacts with 1.0789 of FeCl3
x = 3 * 1.0789 /2 = 1.61835 moles of Mg
Mass of Mg reacted = 1.61835 moles * 24.31 = 39.342 g
Mass of excess Mg = 41 g - 39.342 g = 1.7 g
2.28 Global Warming’s Negative Effects Worksheet
Watch this Video and to answer the following questions.
What type of human activity increases the amount of CO2 in the atmosphere?
Explain how climate change affects our oceans
Explain how climate change affects our weather
Explain how climate change affects our food
Explain how climate change affects our health
What can we do to prevent the negative effects of climate change?
PLEASE ANSWER ASAP GIVE BRAINLIEST
A 6.23 g nugget of pure gold absorbed 282 J of heat. The initial temperature was 30.4 degrees Celsius. What was the correct final temperature of the gold nugget if the specific heat of gold is 0.129 J/gC
Answer:
Final temperature, T2 = 381.28°C
Explanation:
Given the following data;
Mass = 6.23 g
Initial temperature = 30.4°C
Heat capacity = 282 J
Specific heat capacity = 0.129 J/g°C
To find the final temperature;
Heat capacity is given by the formula;
[tex] Q = mcdt[/tex]
Where;
Q represents the heat capacity or quantity of heat.
m represents the mass of an object.
c represents the specific heat capacity of water.
dt represents the change in temperature.
Making dt the subject of formula, we have;
[tex] dt = \frac {Q}{mc} [/tex]
Substituting into the equation, we have;
[tex] dt = \frac {282}{6.23*0.129} [/tex]
[tex] dt = \frac {282}{0.8037} [/tex]
dt = 350.88°C
Now, the final temperature T2 is;
But, dt = T2 - T1
T2 = dt + T1
T2 = 350.88 + 30.4
Final temperature, T2 = 381.28°C
Propane is an alkene. Describe the test for alkenes. Give the colour change in the test.
Answer:
Explanation:
One test for Alkenes is testing with bromine water. This test can be used to tell the difference between an Alkanes and Alkenes. On a normal, any Alkene will turn brown bromine water to colourless because the bromine reacts with the double carbon-carbon bond. Also, the reaction takes place with unsaturated compounds that contains the double carbon-carbon bonds.
Conversely, when Alkanes go through the same test, there is no reaction with bromine water.
_Ch7H16+_O2=_CO2+_H2O balancing the equation
Answer:
0,11,7,8
Explanation: hope this helps!
If an amine functional group is added to an organic compound, the name of the compound will begin with
Answer for a apple it would be happle
xplanation:
Which reaction type? *
combination (synthesis)
combustion
decomposition
single replacement
double replacement
What are the consequences of purposely having an excess of one of the reactants?
Answer:
When one reactant is in excess, there will always be some left over. The other reactant becomes a limiting factor and controls how much of each product is produced. While using excess reactants can help to increase percentage yields, this is at the expense of atom economy.
Explanation:
4. Based on their placement on the periodic table, which of the following is more
reactive?
A.Sodium (Na)
B. Magnesium (Mg)
C. Barium (Ba)
D. Neon (Ne)
What are the only types of metals that be magnetized?
In your own words, describe how the moon’s gravity affects the tides.
Answer:
It makes them splash more.
Explanation:
Answer:
Tidal force
Explanation:
The moon's gravitational pull generates the tidal force. The tidal force causes Earth, more specifically Earth's water to bulge out on the side closest and farthest from the moon. These are high tides.
hope this helps:)
Why do the two electrons spend their time equally between both hydrogen atoms? In other words, why can’t one hydrogen just take the other’s electron?
Helllpppp I will give you branliest!!! In which cell organelle is DNA found?
Answer:
nucleus
Explanation:
Answer:
Found in the nucleus
Explanation:
I hope this answer is correct and helpful!
21. An object appears blue when seen in sunlight. The same object is illuminated by a mixture of equally bright red and green light. It is also viewed through a blue filter. What color does the object appear to be? A. Blue B. Cyan C. Black D. Green
Answer: Green.
Explanation: Because object appears to be blue in sunlight, it absorbs counter colour of blue, also orange-red colour. So, when illuminated with
red-green colour, red light is more absorbed and object appears to be green.
Which of the following factors affects the amount of heat absorbed by a substance?
A. Boiling point of the substance
B. Specific heat capacity of the substance
C. Melting point of the substance
D. Shape of the substance
Answer:
The correct answer is B, "Specific heat capacity of the substance."
Explanation:
I just took the test. I hope this helps!
Heat absorbed changes the bonds of the molecules or the compounds to alter their state. The specific heat capacity affects the amount of heat absorbed. Thus, option B is correct.
What is specific heat capacity?Specific heat capacity is defined as the amount of heat or energy absorbed by the kilogram of the solid reactant when the system experiences a rise in temperature. It is measured in J/(kg K) or J/(kg °C).
The specific heat capacity, the mass of the substance, temperature, and the phase of the substance affects the absorption of the heat from the surrounding. The specific heat affects absorption as it tells about the substance's ability to take the heat energy.
Therefore, specific heat capacity affects heat absorption.
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How do ecosystems change overtime
Answer:
Ecosystems, the interactive system of living and nonliving organisms in a specific location, change slowly over time. When new plants and animals arrive in an area, they either thrive or struggle. Thriving species sometimes displace native species. When this happens, the system as a whole begins to change.
A student dissolves 10 grams of sugar in enough water to make 25 ml of solution. What is the concentration of the solution
Answer: The concentration of given solution is 11.68 M.
Explanation:
Given: Mass of solute = 10 g
Volume of solution = 25 mL
Convert mL into L as follows.
[tex]1 mL = 0.001 L\\25 mL = 25 mL \times \frac{0.001}{1 mL}\\= 0.025 L[/tex]
Number of moles is the mass of substance divided by its molar mass. The moles of sugar (molar mass = 342.3 g/mol) is as follows.
[tex]No. of moles = \frac{mass}{molar mass}\\= \frac{10 g}{342.3 g/mol}\\= 0.0292 mol[/tex]
Molarity is the number of moles of solute present in a liter of solution.
Hence, concentration of given solution is calculated as follows.
[tex]Molarity = \frac{no. of moles}{Volume (in L)}\\= \frac{0.0292 mol}{0.025 L}\\= 11.68 M[/tex]
Thus, we can conclude that the concentration of given solution is 11.68 M.
A car travels at 24km/hr to the north. Then it travels 24km/hr to the east. Which is true about the car's acceleration?
a
The car accelerated because it speed increased.
b
The car accelerated because it changed direction.
c
The car did not accelerate because its speed did not change.
d
Only the velocity changed, not the acceleration not the acceleration.
Answer:
D
Explanation:
What are some of the issues facing the ocean ( give at least 3 )
Answer:
Pollution
Overpopulation
Destruction of habitats
Explanation:
Hydrologers study the availability of fresh water on the planet.
Answer:
Hydrologists study how water interacts with the earth's crust. For example, they may study how rainfall and snowfall cause erosion, create caves, percolate through soil and rock to become groundwater, or eventually reach the sea.Hydrologists strive to improve water quality and increase our access to water so that we can continue to make use of it in all the ways that are necessary to our lives. A hydrologist measures the stream flow in a tributary to the Coeur d'Alene River. layers of gases surrounding a planet or other celestial body