Answer:
We do something called hypothesis
Answer:
1. Make an observation.
2. Ask a question.
3. Propose a hypothesis.
4. Make predictions.
5. Test the predictions.
6. Iterate.
and if it can't be trsted the you did something wrong
Explanation:
The scientific method
At the core of biology and other sciences lies a problem-solving approach called the scientific method. The scientific method has five basic steps, plus one feedback step:
Make an observation.
Ask a question.
Form a hypothesis, or testable explanation.
Make a prediction based on the hypothesis.
Test the prediction.
Iterate: use the results to make new hypotheses or predictions.
The scientific method is used in all sciences—including chemistry, physics, geology, and psychology. The scientists in these fields ask different questions and perform different tests. However, they use the same core approach to find answers that are logical and supported by evidence.
Scientific method example: Failure to toast
Let's build some intuition for the scientific method by applying its steps to a practical problem from everyday life.
What is an example of a physical change?
A. having less ash than the paper that was burned to form it
B. ice forming and then melting back into water
C. rust having a different identity than the iron it forms on
D. the irreversible reaction of vinegar and baking soda
What one would you guys choose?
Answer:
B is correct answer
Explanation:
Answer:
B.
Explanation:
What is a single covalent bond?
Answer: Single Covalent Bonds
Hydrogen and chlorine coming together is an example of a single covalent bond. Two hydrogen atoms will also come together to form a single covalent bond, as will two chlorine atoms. In these examples, each individual atom has just one unpaired electron to share with the other atom.
A Little Backstory I Guess: In chemistry, a single bond is a chemical bond between two atoms involving two valence electrons. That is, the atoms share one pair of electrons where the bond forms. Therefore, a single bond is a type of covalent bond.
sorry its so long :/ hope this even relatively helps...
Is matter smooth and continuous?
Answer:
YES,Explanation:
Matter is smooth and continuous. ... A liquid has a definite volume; but it has no definite shape.i am timed please help
Answer:
mixture
Explanation:
there was leftover components meaning there was something mixed into the liquid
I have a buddy who recycles electronics, and isolates metals from the connector pins electrical boards. He isolates gold, for example, and purifies it the best he can, then sells it along with his other scrap metal. This last go around he was able to isolate 3.00 g of Au with a process he claims results in a 80.0% yield. If he is correct, what was his theoretical yield
Answer:
Theoretical yield = 3.75g
Explanation:
Percent yield is defined as one hundred times the ratio between actual yield and theoretical yield. The expression is:
Percent yield = Actual Yield / Theoretical Yield * 100
In the problem, your actual yield was 3-00g.
Percent yield is 80.0%.
Solving for theoretical yield:
80% = 3.00g / Theoretical yield * 100
Theoretical yield = 3.00g / 80.0% * 100
Theoretical yield = 3.75g6.300x10-5 – 7.200x10-3
Answer:
-17
Explanation:
6300/1000×10-5-7200/1000×10-3
63000/1000-5-72000/1000-3
63-5-72-3
-17
the coefficient is -7.137 but i’m not sure what the exponent is, i’m sorry :/
A peregrine falcon dives 176 meters through the air in 8 seconds. Its
average speed during the dive is 22 m/s. *
Answer:
This question is asking to find the average speed during the dive. The answer is 22m/s.
Explanation:
Average speed of a substance can be calculated knowing it's distance over a particular amount of time.
The formula for average speed is:
Average speed (s) = Distance (d) / time (t)
In the case of this question where A peregrine falcon dives 176 meters through the air in 8 seconds, the distance of the falcon is 176m, while the time is 8s. Hence;
Average speed = 176/8
Average speed = 22
Therefore, the average speed of the falcon diver is 22m/s.
Which of the alkyne addition reactions below involve(s) an enol intermediate?
1) halogenation.
2) hydrogen in the presence of a metal catalyst.
3) hydroboration/oxidation.
4) none of the above.
The correct answer is (3): hydroboration/oxidation.
Hydroboration/oxidation of alkynes involve an enol intermediate.
An intermediate is a specie that occurs along the steps of a non-elementary reaction but does not appear among the products.
Hydroboration refers to the reaction of borane (BH3) with alkyne. The addition of borane to an alkyne passes through an enol intermediae and the same also goes for oxidation of an alkyne.
Hence, hydroboration/oxidation are alkyne addition reactions that involve enol intermediate. The mechanism of hydroboration is shown in the image attached.
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The density of ice is 0.917 g/cm3. What volume of ice does 52.75 g occupy?
Answer:
The answer is
57.52 mLExplanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} [/tex]
From the question
mass of ice = 52.75 g
density = 0.917 g/cm³
The volume of the ice is
[tex]volume = \frac{52.75}{0.917} \\ = 57.52453653[/tex]
We have the final answer as
57.52 mLHope this helps you
6.(01.05 LC) Which states of matter change shape when moved?(2 points) Gases and solids Liquids and gases Liquids, solids, and gases Solids and liquids
Answer:Gases and solids , Solids and liquids
Explanation:
A solid has a definite shape while liquids and gases take the shape of the container in which they are found .
Hence when a substance changes it's state from gas to solid or solid to liquid, it's shape automatically changes as explained above.
28 Which of the following equations does not represent a redox reaction?
A
B
с
D
2AgBr (s) → 2Ag (s) + Br2 (g)
Cu2+ (aq) + Zn (s) → Cu (s) + Zn2+ (aq)
2Fe (s) + 3Cl2 (9) ► 2FeCl3 (s)
MgO (s) + 2HCl (aq) → MgCl2 (aq) + H20 (1
Answer:
The answer is D. In the reactions A,B and C the reactants undergo changes in oxidation number. And also the reaction D is an acid_base neutralization reaction.
An atomic model shows 19 protons, 20 neutrons, and 19 electrons. What is the mass number of the atom?
The elemental analysis of an organic solid extracted from gum arabic showed that it contained 40.0% C, 6.7% H, and 53.3% O. A solution of 0.650 g of the solid in 27.8 g of the solvent diphenyl gave a freezing point depression of 1.56 °C. Calculate the molar mass and determine the molecular formula of the solid (kf for diphenyl is 8.00 °C/m). To earn full credit, clearly show your work with units and proper significant figures
Answer:
The molar mass of the organic solid is 119.9g/mol.
The molecular formula of an organic solid is C4H8O4
Explanation:
Step 1
We find the Molar mass
From the above question, we are given:
A solution of 0.650 g of the solid in 27.8 g of the solvent diphenyl gave a freezing point depression of 1.56 °C. Calculate the molar mass and determine the molecular formula of the solid (kf for diphenyl is 8.00 °C/m)
A freezing point depression = 1.56 °C.
Mass of organic solid= 0.650 g
Mass of diphenyl = 27.8 g
Converting to kilograms
1000g = 1kg
27.8g =
Cross Multiply
= 27.8g × 1 kg/1000g
= 0.0278kg
Boiling point constant = 8.00 °C/m
Molar mass of the organic compound = Boiling point constant × Mass of solid /Freezing point depression × Mass of diphenyl
Molar mass of the organic compound =
8.00 °C/m × 0.650g/1.56°C × 0.0278kg
= 5.2 g°C/m ÷ 0.043368 g°C
= 119.9040767 g/mol
Approximately = 119.9 g/mol
Step 2
Find the Molecular formula
Molecular formula = CxHyOz
Let x = Carbon, y = Hydrogen, z = Oxygen
For x = Carbon
Atomic mass of Carbon = 12.01078
x = % of Carbon in the compound × Molar mass of the organic compound/atomic mass of Carbon
x = 40% × 119.9 g/mol / (12.01078
x = 3.99
x = Approximately = 4
For y = Hydrogen
Atomic mass of Hydrogen = 1.007947
y = % of Hydrogen in the compound × Molar mass of the organic compound/Atomic mass of Hydrogen
x = 6.7% × 119.9 g/mol) / 1. 007947
x = 7.97
x is Approximately = 8
For z = Oxygen
Atomic mass of Oxygen = 15.99943
z = % of Oxygen in the compound × Molar mass of the organic compound/Atomic mass of Oxygen
z = 53.3% × 119.9 g/mol /15.99943
z = 3.99
z is approximately ≈ 4
Therefore,
The molar mass of the organic solid is 119.9 g/mol.
The molecular formula of an organic solid is C4H8O4
15.0 g of water is heated from 5 °C up to 37 °C. How much energy is absorbed by
the water? (The specific heat of liquid water is 4.184 J/g °C.)
Answer:
See the answer
1) 15.0 g of water is heated from 5 °C up to 37 °C. How much energy is absorbed by the water? (The specific heat of liquid water is 4.184 J/g°C.)
2)How many joules of energy is required to bring a five-pound (1 pound = 454 g) bag of ice from its freezer temperature at -20.0°C up to 0°C? The specific heat of ice is 2.10 J/g×°C.
3) A 50.0 mg tissue sample is taken from a patient for diagnosis. While waiting for testing, the sample is stored in a -80.0°C freezer. How much energy is released when the sample is cooled from 20.0°C down to the freezer temperature? You may assume the specific heat of the tissue sample is 3.47 J/g×K.
What is the mass of 87.94 mL of ethanol, which has a density of 0.79 g/mL?
Answer:
The answer is
69.47 gExplanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volumeFrom the question
volume of ethanol = 87.94 mL
density = 0.79 g/mL
The mass of ethanol is
mass = 87.94 × 0.79
mass = 69.4726
We have the final answer as
69.47 gHope this helps you
Which of the reactions are spontaneous (favorable)?
A. 2Mg(s) + O2(g) rightarrow 2MgO (s) delta G = - 1137 kJ / mol
B. NH3(g) + HCl(g ) rightarrow NH4Cl(s) delta G = - 91.1 kJ / mol
C. AgCl(s) rightarrow Ag+ (aq) + Cl-[aq) delta G = 55.6 kJ / mol
D. 2H2(g) + O2(g) rightarrow 2H2O(g) delta G= 456 kJ / mol
E. C(s) + H2O(t) rightarrow CO(g) + H2(g) delta G = 90.8 kJ / mol
F. CH4(g) + 2O2(g) rightarrow CO2(g) + 2H2O(t) delta G = -820 kJ / mol
A. Reaction A.
B. Reaction B.
C. Reaction C.
D. Reaction D.
E. Reaction E.
F. Reaction F.
Answer: Reactions: A, B and F
Explanation: Gibbs Free Energy, symbol G, combines Enthalpy (sum of internal energy) and Entropy (measure of how much the energy of atoms and molecules become spread out in a process).
The change in free energy (ΔG) is the sum of enthalpy and the product of temperature and entropy of the system.
With free energy, it is possible to determine if a reaction is spontaneous, i.e., happens wthout external energy, or non-spontaneous.
If ΔG is negative, reaction is spontaneous. If ΔG is positive, reaction is non-spontaneous.
Analysing each ΔG of the reactions above, reactions A, B and F's Gibbs Free energy are negative, so these 3 are spontaneous.
Jack has a rock. The rock has a mass of 14 g and a volume of 2 cm3. What is the density of the rock? * 0 7 ml O 28 g/cm3 07 g/cm3 O 1/7 g/cm3
Answer:
The answer is
7.0 g/cm³Explanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
From the question
mass of rock = 14 g
volume = 2 cm³
The density of the rock is
[tex]density = \frac{14}{2} \\ [/tex]
We have the final answer as
7.0 g/cm³Hope this helps you
A ratio that compares the length and width of a garden is what type of model?
A. Physical
B. Conceptual
C. Computer
D. Mathematical
Answer:
D. Mathematical
Explanation:
Where did I go wrong? I know the 2.58 is the right answer but where did I go wrong in my work? Please help!!
Answer: See below
Explanation:
In this problem, conversion factors are very important. In the second conversion, you wrote 1 kg=0.001 g. This is incorrect. It should be 1 kg=1000g. Otherwise, the rest is correct. Make sure to have correct conversions. The answer will be correct.
Calculate the mass (in grams) of 0.473 mol of titanium
Explanation:
n=given mass ÷molar mass
make given mass become the subject of the formula by
multiplying the molar mass on both sides of the equation.
n=0.473mol
given mass=??
molar mass=48
therefore,given mass=n×molar mass
=0.473×48
=22.704grams
mass in grams is 22.704grams
The mass (in grams) of 0.473 mol of titanium is 22.6 grams.
We have some specific amount of moles of titanium.
We have to calculate the mass of given sample of titanium.
What is Titanium ?Titanium is a chemical element with the symbol Ti and atomic number 22. It is found in nature only as an oxide.
According to the question -
Moles of titanium - 0.473 moles.
Mass of 0.473 moles of titanium =
0.473 moles titanium x (47.87 grams titanium / 1 mole) = 22.6 grams
Hence, the mass (in grams) of 0.473 mol of titanium is 22.6 grams.
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Complete the autoionization reaction for water.
H2O + H2O
Answer:
Self ionization and self dissociation both are the process of ionization of the water.
Explanation:
The ionization process occur in pure water. This process occur when water is in aqueous form, where the water molecules like H2O will deprotonates and to form a hydroxide ions OH-.
It immediately protonates another molecule with water such as H+. It makes hydronium such as H3O+. It is also called auto protolyzes.
Such as an example:
H2O +H2O = H3O+ + OH-
The complete equation for the autoionization of water is
H₂O + H₂O ⇌ H₃O⁺ + OH⁻
From the question,
We are to complete the autoionization reaction for water
First, we will explain what is meant by autoionization reaction of water
Autoionization reaction of water also known as self-ionization of water is an ionization reaction in pure water or in an aqueous solution, in which a water molecule, H₂O, deprotonates to become a hydroxide ion, OH⁻. The proton, H⁺, immediately protonates another water molecule to form hydronium, H₃O⁺.
The equation for the reaction is
H₂O + H₂O ⇌ H₃O⁺ + OH⁻
Hence, the complete equation for the autoionization of water is
H₂O + H₂O ⇌ H₃O⁺ + OH⁻
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A state of dynamic equilibrium, Ag2CO3(s) 2Ag^+(aq) + CO3^2-, exists in solution.
What shift occurs in the equilibrium if HCl (aq) is added to the system? Explain please
Answer:
The equilibrium will shift to the right producing more Ag⁺ and CO₃²⁻
Explanation:
In the equilibrium:
Ag₂CO₃(s) ⇄ 2Ag⁺(aq) + CO₃²⁻(aq)
The change in concentration of Ag⁺ or CO₃²⁻ will shift the equilibrium
The addition of HCl(aq) (Dissociates in H⁺ and Cl⁻ ions) produce the formation of AgCl. The reaction is:
Ag⁺(aq) + Cl⁻(aq) ⇄ AgCl(s)
That means the addition of HCl decrease concentration of Ag⁺.
Based on LeChatelier's principle: As the Ag⁺ decreases, the equilibrium will decrease amount of Ag₂CO₃ producing more Ag⁺ and CO₃²⁻. That is:
The equilibrium will shift to the right producing more Ag⁺ and CO₃²⁻
An object is a regular, rectangular, solid with dimensions of 2 cm by 3cm by 2cm. It has a
mass of 24 g. Find its density.
Answer:
2
Explanation:
Density = mass/volume
m=24
v=2*3*2=12
24/12=2
Answer:
[tex]\boxed {\tt d= 2 \ g/cm^3}[/tex]
Explanation:
Density can be found using the following formula.
[tex]d=\frac{m}{v}[/tex]
where [tex]m[/tex] is the mass and [tex]v[/tex] is the volume.
We know the mass is 24 grams. We must find the volume.
Since it is a rectangle, the volume can be found using the following formula.
[tex]v=l*w*h[/tex]
The length is 2 centimeters, the width is 3 centimeters and the height is 2 centimeters.
[tex]v= 2 \ cm * 3 \ cm * 2\ cm[/tex]
[tex]v= 6 \ cm^2 * 2\ cm[/tex]
[tex]v= 12 \ cm^3[/tex]
Now we know the volume, and can substitute it into the density formula.
[tex]d=\frac{m}{v}[/tex]
[tex]m= 24 \ g\\v= 12 \ cm^3[/tex]
[tex]d=\frac{24 \ g}{12 \ cm^3}[/tex]
[tex]d= 2 \ g/cm^3[/tex]
The density is 2 grams per cubic centimeter.
How do the coefficients in a balanced equation compare quantities of two
substances?
O A. The ratio of the coefficients equals the ratio of the masses of the
substances
O B. The sum of the coefficients of the reactants equals the sum of the
products
O C. The ratio of the substances' coefficients equals the ratio of their
number of moles.
OD. The coefficient of the reactant tells how many product molecules
will form.
Answer:
C. The ratio of the substances coefficients equal the ratio is the number of moles
Explanation:
The ratio of the substances' coefficients equals the ratio of their
number of moles. Hence, option C is correct.
What are moles?A mole is defined as 6.02214076 × [tex]10^{23}[/tex]of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.
Mole ratios are used as conversion factors between products and reactants in many chemistry problems.
The mole ratio may be determined by examining the coefficients in front of formulas in a balanced chemical equation.
Also known as the mole ratio is also called the mole-to-mole ratio.
Hence, option C is correct.
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Estimate the volume of the football. Compare the football to the table tennis balls by dragging the football over the
table tennis balls to assess its size.
The mass of the tennis balls are 2.7(g)
Answer:
4,300
Explanation:
4,300..
Hope this helps ..Be sure to answer all parts. Calculate the mass of each product formed when 70.76 g of diborane (B2H6) reacts with excess water: B2H6(g) + H2O(l) → H3BO3(s) + H2(g) [unbalanced] Mass of H3BO3: g Mass of H2: g
Answer:
A. 313.37 g of H3BO3.
B. 30.33 g of H2.
Explanation:
We'll begin by writing a balanced equation for the reaction. This is given below:
B2H6 + 6H2O → 2H3BO3 + 6H2
Next, we shall determine the mass of B2H6 that reacted and the masses of H3BO3 and H2 produced from the balanced equation equation. This can be obtained as follow:
Molar mass of B2H6 = (2×11) + (1×6) = 22 + 6 = 28 g/mol
Mass of B2H6 from the balanced equation = 1 × 28 = 28 g
Molar mass of H3BO3 = (1×3) + 11 + (3×16) = 3 + 11 + 48 = 62 g/mol
Mass of H3BO3 from the balanced equation = 2 × 62 = 124 g
Molar mass of H2 = 2×1 = 2 g/mol
Mass of H2 from the balanced equation = 6 × 2 = 12 g
From the balanced equation above:
28 g of B2H6 reacted to produce 124 g of H3BO3 and 12 g of H2.
A. Determination of the mass of H3BO3 produced from the reaction.
This can be obtained as follow:
From the balanced equation above,
28 g of B2H6 reacted to produce 124 g of H3BO3.
Therefore, 70.76 g of B2H6 will react to produce = (70.76 × 124)/28 = 313.37 g of H3BO3.
Therefore, 313.37 g of H3BO3 were obtained from the reaction.
B. Determination of the mass of H2 produced from the reaction.
This can be obtained as follow:
From the balanced equation above,
28 g of B2H6 reacted to produce 12 g of H2.
Therefore, 70.76 g of B2H6 will react to produce = ((70.76 × 12)/28 = 30.33 g of H2.
Therefore, 30.33 g of H2 were obtained from the reaction.
ZnO
Express your answer as an ion?
Answer:
[tex]Zn^{2+}[/tex]
Explanation:
Hello,
In this case, since metals tend to lose electrons, they usually become the cations when chemical compounds are formed so the other element should be negative to allow their interactions to take place.
In such a way, since oxygen is known to be negatively charged as -2 and their subscripts are both 1, we infer that the oxidation state of zinc is +2, therefore, it is written as an ion as follows:
[tex]Zn^{2+}[/tex]
Best regards.
An element has a mass number of 9 and 5 neutrons. What element is it?
Answer:
Fluorine
Fluorine is the element in question, as its atomic number is 9 . You would name this particular isotope using the mass number. It would be called fluorine-19.
Explanation:
Answer:
Fluorine
Fluorine is the element in question, as its atomic number is 9 . You would name this particular isotope using the mass number. It would be called fluorine-19.
Chlorine could combine with _ to gain the extra electron it needs to stabilize its outer shell
outer shell.
A. helium
B. sulfur
C. hydrogen
D. none of these
Answer:
C, hydrogen.
Explanation:
I am timed please help!!
Answer:
it is a mixture
element are pure and compound are formed in a fixed ratio
Explanation: