1. Questions that can be answered using science include:
- Does water exist on Venus?
- Should the use of automobiles be stopped?
2. Based on scientific knowledge, the most favorable day for Sarah to go on an outing would be Wednesday, as the air pressure started rising on the fourth day, indicating improving weather conditions.
3. Questions that can be answered using scientific methods include:
- What would be the effect of a hurricane?
4. Predictions about the future based on the lines on the palm of the hand is an example of pseudoscience.
5. The idea that Earth is becoming warmer will become unacceptable over time if scientific evidence supports a new idea.
6. Science helps society by helping society take reasonable decisions.
7. A theory is accepted by scientists when it is supported by adequate data.
The next step for the scientist who discovered a new theory on the evolution of the universe would be to inform the scientific community so they can verify the results.
8. A model of a widely accepted theory about the position of planets and sun would most likely help the scientist to understand facts which cannot be easily observed.
What volume of 0.12M Ba(OH)2 is needed to neutralize 12.2 mL of 0.25M HCl? *
25 ml
13 ml
50ml
125 ml
50 ml es el resultado
To neutralize 12.2 mL of 0.25M HCl, approximately 12.7 mL of 0.12M Ba(OH)2 is required. The closest option provided is 13 mL, which is correct based on the stoichiometry of the reaction and the concentrations involved.
Explanation:To determine the volume of 0.12M Ba(OH)2 needed to neutralize 12.2 mL of 0.25M HCl, we must first write out the balanced chemical equation for the reaction:
Ba(OH)2 (aq) + 2 HCl (aq) → BaCl2 (aq) + 2 H2O (l)
From the equation, we see that one mole of Ba(OH)2 reacts with two moles of HCl. Next, we calculate the number of moles of HCl that will be neutralized:
Moles of HCl = Volume (L) × Concentration (M)
Moles of HCl = 0.0122 L × 0.25 M = 0.00305 mol
Based on the stoichiometry of the balanced equation, we need half the number of moles of Ba(OH)2 to neutralize the HCl.
Moles of Ba(OH)2 = 0.00305 mol HCl × (1 mol Ba(OH)2/2 mol HCl) = 0.001525 mol
Then, we calculate the volume of Ba(OH)2 solution:
Volume of Ba(OH)2 = Moles of Ba(OH)2/Concentration of Ba(OH)2
The volume of Ba(OH)2 = 0.001525 mol/0.12 M = 0.012708 L, which is approximately 12.7 mL.
Therefore, the volume of 0.12M Ba(OH)2 needed to neutralize 12.2 mL of 0.25M HCl is closest to 13 mL, which is one of the given options.
Learn more about Acid-Base Titration here:https://brainly.com/question/40172894
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A tree was chopped down and cut up in a local forest. The tree changed in shape.
Which kind of change took place?
A. change in reaction
B. phase change
C. physical change
D. chemical change
Answer would be C, Physical Change, it's similar to crumpling up a piece of paper
physical change is the answer
What is the molar concentration of the acid if 35.18 mL of hydrochloric acid was required to neutralize 0.745 g of ALUMINUM hydroxide?
The solution will be 0.27M hydrochloric acid
In the final chemical equation, NaCl and O2 are the products that are formed through the reaction between Na2O and Cl2. Before you can add these intermediate chemical equations, you need to alter them by
the answer to the question is b
Answer : The correct option is, (B) multiplying the equation first by 2.
Explanation :
The balanced final chemical reaction will be,
[tex]2Na_2O(s)+2Cl_2(g)\rightarrow 4NaCl(s)+O_2(g)[/tex]
The two intermediate chemical reaction are give :
(1) [tex]2Na(s)+Cl_2(g)\rightarrow 2NaCl(s)[/tex]
(2) [tex]2Na_2O(s)\rightarrow 4Na(s)+O_2(g)[/tex]
First multiplying the equation (1) by 2, we get
[tex]4Na(s)+2Cl_2(g)\rightarrow 4NaCl(s)[/tex]
Now adding both the equations, we get
[tex]2Na_2O(s)+4Na(s)+2Cl_2(g)\rightarrow 4Na(s)+O_2(g)+4NaCl(s)[/tex]
The final chemical reaction are :
[tex]2Na_2O(s)+2Cl_2(g)\rightarrow 4NaCl(s)+O_2(g)[/tex]
Hence, the correct option is, (B) multiplying the equation first by 2.
I need help ASAP
1.Minerals are generally (2 points)
A.solids
B.liquids
C.gases
D.plasmas
2.Which of these statements is correct about water and oil? (2 points)
A.Water is not a mineral because it is a liquid but oil is a mineral because it is formed under the ground by natural processes.
B.Both water and oil are minerals because they are natural materials with a definite chemical composition.
C.Water is a mineral because it has a definite chemical composition but oil is not a mineral because it is organic.
D.Both water and oil are not minerals because they are liquids
3.What mineral is most likely used to make the plumbing pipe? (2 points)
A.talc
B.zinc
C.quartz
D.copper
4.Which of these is the correct next step to complete the diagram? (2 points)
A.Put an arrow labeled cools and crystallizes, pointing from igneous rocks to sediments.
B.Put an arrow labeled cools and crystallizes, pointing from sedimentary rocks to sediments.
C.Put an arrow labeled heat and pressure, pointing from igneous rocks to metamorphic rocks.
D.Put an arrow labeled heat and pressure, pointing from metamorphic rocks to sedimentary rocks.
5.
Igneous rocks are formed due to the (2 points)
A..cooling of magma
B.weathering of rocks
C.changes in pressure
D.changes in temperature
6.David plans to grow corn on his farm. Corn grows best in clay loam soil. Which of these is the most likely soil sample that David would select to grow corn? (2 points)
A.sample containing 30 percent sand, 35 percent clay, and 35 percent silt
B.sample containing 25 percent sand, 15 percent clay, and 60 percent silt
C.sample containing 40 percent sand, 15 percent clay, and 45 percent silt
D.sample containing 55 percent sand, 30 percent clay, and 15 percent silt
1. a
2. d
3. d
4. c
5. a
6. a
Answer:
A.solids
D.Both water and oil are not minerals because they are liquids
D.copper
C.Put an arrow labeled heat and pressure, pointing from igneous rocks to metamorphic rocks.
A..cooling of magma
A.sample containing 30 percent sand, 35 percent clay, and 35 percent silt
How many moles are contained in 3.131 x 10^24 particles?
.5 moles.... because 1mole has 6.022×10^23 particles
Answer:
.5
Explanation: just trust
Chalcopyrite, the principal ore of copper (Cu), contains 34.63 percent Cu by mass. How many atoms of Cu can be obtained from 5.11 x 103 kg of ore? A) 1.68 x 1028 Cu atoms B) 1.68 x 1025 Cu atoms C) 6.77 x 1031 Cu atoms D) 6.77 x 1034 Cu atoms
Answer:
A) 1.68 x 10²⁸ Cu atoms.
Explanation:
∵ The mass of Cu in the chalcopyrite ore = mass of the ore x weight fraction of Cu.
Weight fraction of Cu = Weight % / 100 = 34.63 /100 = 0.3463.∴ The mass of Cu in the chalcopyrite ore = mass of the ore x weight fraction of Cu = (5.11 x 10³ kg)(0.3463) = 1.77 x 10³ kg.
We need to calculate the no. of moles of Cu atoms:n of Cu = mass/atomic mass of Cu = (1770 x 10³ g) / (63.54 g/mol) = 27.853 x 10³ mol.
We have that every mole of an element contains Avogadro's no. of atoms (6.022 x 10²³).∴ 27.853 x 10³ mol of Cu contains = (27.853 x 10³ mol)(6.022 x 10²³) = 1.677 x 10²⁸ Cu atoms ≅ 1.68 x 10²⁸ Cu atoms.
What is the number of moles of solute in 250 mL of a 0.4 M solution? Don't forget the unit.
Using the equation we get something like this:
M = moles of solute/ liters of solution
But we need the number of moles of solute right? so we gotta arrange the equation to make it fit our needs.
M x liters of solution = moles of solute
M = mol/L
Liters of solution = L
moles of solute = mol
We have the M which stands for the molar mass in mol/L (0.4M)
And we also have the mL which are the liters of our solution, yet to be converted into liters. Let's divide them by a 1000 to make it into liters.
250mL / 1000 = 0.250L
Now we can multiply them! and find the number of moles of solute by replacing them, remember M can be changed into m/mol, because it's pretty much the same but written in another way.
0.4mol/L x 0.250L = 0.1 mol
The liters canceled, and we end up with mol. So, the answer is 0.1 mol.
Answer: 0.1 mol
Explanation: For gradpoint :)
98 POINTS!
Based on the data (below)
1) which reaction is the most efficient and why?
2) which reaction data is in error and what is the correction?
1) Number of moles of product, carbon dioxide, is the same as that of vinegar. So the most efficient reaction is the one with the less amount of baking soda. So RXN 1 is the most efficient.
2) Number of moles of product, carbon dioxide, is the same as that of vinegar; except RXN 5. There is an error in the number of moles of carbon dioxide. It should be 0.05034.
Answer:
1) 1 is most efficient
Explanation:
efficiency is the ratio bet. reactants n products. adding vinegar n baking soda then dividing by co2, 1 gives the largest no.
2) 5 has different vinegar n co2 ratio - they are the same in the other 4. so for 5, the co2 should be 0.05034.