Answer:
²⁸Mg
Explanation:
12 electrons means it is a Mg;
A typical Mg has 12 neutrons, but this has 16 hence it must be an isotope with 4 extra neutrons.
How many grams are equal to 0.11 mole of copper(I) chromate?
Mass of Copper(I) chromate( CuCrO₄) = 19.75 g
Further explanationThe mole is the number of particles contained in a substance
1 mol = 6.02.10²³
Moles can also be determined from the amount of substance mass and its molar mass
[tex]\tt \large{\boxed{\bold{mol=\dfrac{m(mass)}{MW(molecular~weight)}}}[/tex]
0.11 mole of Copper(I) chromate( CuCrO₄) ⇒ MW=179.54 g/mol, so mass :
[tex]\tt mass=mol\times MW\\\\mass=0.11\times 179.54\\\\mass=19.75~g[/tex]
A chemistry teacher is able to grade chemistry labs at a rate of 5 labs for every 3 minutes. They need to grade 165 labs how many hours will it take?
Answer:
1.65hr
Explanation:
Given parameters:
Number of labs = 5 labs
Time taken = 3 minutes
Unknown:
Time taken in hours to grade 165 labs = ?
Solution:
Let us find the rate of the teacher;
Rate = [tex]\frac{number of labs}{time}[/tex]
Insert the parameters and solve;
Rate = [tex]\frac{5}{3}[/tex] = 1.67labs/min
Now;
Time to grade 165 labs = [tex]\frac{number of labs}{rate}[/tex]
Time to grade 165 labs = [tex]\frac{165}{1.67}[/tex] = 98.8min
Since;
60min = 1hr
98.8min = [tex]\frac{98.8}{60}[/tex] = 1.65hr
Use the model to answer the question.
Which element symbol actually represents the model?
Plz answer
Answer:
B
Explanation:
Boron has 5 protons.
Which of the following best describes a hypothesis?
A. An explanation that is supported by scientific data
B. A proven explanation for experimental results
c. A possible answer to a scientific question
D. A question about the natural world
please help i will give brainliest
calculate the ph of a solution whose(oh^-) is 4.583*10^-5 mole dm cube (pkw=14)
pH of solution = 9.661
Further explanationpH is the degree of acidity of a solution that depends on the concentration of H⁺ ions. The greater the value the more acidic the solution and the smaller the pH.
pH = - log [H⁺]
So that the two quantities between pH and [H⁺] are inversely proportional because they are associated with negative values.
pOH=-log[OH⁻]
[tex]\tt pOH=-log[4.583\times 10^{-5}]\\\\pOH=5-log~4.583=4.339[/tex]
pH+pOH=pKw
[tex]\tt pH=14-4.339\\\\pH=9.661[/tex]
List the elements that make up the compound copper sulfate
Given the following equation,
HCl aq) + NaOH aq
NaClaq) + H2O(l)
How many moles of H20 will be produced if there are 5 moles of HCI?
Answer:
5 moles
Explanation:
Given data:
Number of moles of HCl = 5 mol
Number of moles of H₂O produced = ?
Solution:
Chemical equation:
HCl + NaOH → NaCl + H₂O
Now we will compare the moles of HCl with H₂O.
HCl : H₂O
1 : 1
5 : 5
5 moles of water will be produced.
What will happen to the flow of blood in blood vessels (pulse) if heart beat rate increase
Answer:
"Low levels of the hormone epinephrine, also called adrenaline, cause blood vessels to relax and widen. High levels of this same hormone, along with the hormone norepinephrine, cause the blood vessels to narrow and the heart rate to rise, increasing blood pressure."
Explanation:
PLEASE HELP ME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! You think that although there are some differences, the human nervous system is similar to a computer. You're friend says, "No way! A computer is just metal, wires, and plastic." Develop an argument that would persuade your friend that there are similarities between these two systems. Include specific examples and evidence to support your position.
Answer:
We have nerves that are just like wires that run through our body that tells us what is going on and what to do about it. The hard dive like in a computer is our brain, which is made up of three parts that control things like coordination, movement, involuntary, and voluntary movement. The sensory numerous just like the keys in a computer pick up what we are doing in life.
Explanation:
The equations are not balanced. Which equation would have the same coefficients in the same order as 2CO2 + 3H20 C2H6O + 3O2?
Answer:
Fe + H2SO4 Fe2(SO4)3 + H2
Explanation:
its the answer on my answer key
Answer:
C- Fe + H2SO4 Fe2(SO4)3 + H2
Explanation:
The person above me is right. I also just took the test.
Please Help!!!
Which of the following is not a good indication that a chemical change has occurred?
A. The formation of gases
B. A change in color
C. A scratched surface
D. The release heat or light
Answer:
C.
Explanation:
Which part of the atom can be transferred from one atom to another to form
ions?
a. Protons
b. Neutrons
c. Valence Electron
d. Nucleus
Answer:
Explanation: Valance Electron
wich if the following statements best describes why the mass of a bowling ball would not change if it were transported from earth to the moon?
gravity is constant forge
the bowling ball will adapt to the changes in gravity
matter is resistant and changes gravity
the amount of mattet in the bowling ball remains the same
Answer:
the amount of matter in the bowling ball remains the same
Explanation:
The reason why the mass of the bowling ball on earth and moon remains the same is that matter in the bowling ball remains the same.
Mass of any substance is the amount of matter it contains.
Since there is no loss in matter, the mass of the bowling ball anywhere in the universe will be the same. Only the weight changes due to differences in gravity.Use the drop-down menus to select the sentences that show precise use of pronouns.
1. Fred visited Nick after his graduation.
2. After Nick's graduation, Fred visited him.
1. Marie told Sarah that she makes great spaghetti.
2. Marie told Sarah, "You make great spaghetti."
1. John broke the fence with his bike.
2. John's bike hit a fence and it broke.
Answers
Sentence 1
Sentence2
Answer:
sentence 2, sentence 2, sentence 1
Explanation:
it was right for me on edge 2020
Answer:
1. Fred visited Nick after his graduation.
2. After Nick's graduation, Fred visited him.
1. Marie told Sarah that she makes great spaghetti.
2. Marie told Sarah, "You make great spaghetti."
1. John broke the fence with his bike.
2. John's bike hit a fence and it broke.
5)
Experiments with gold foil indicated that atoms
A)
usually have a uniform distribution of positive charges
B)
usually have a uniform distribution of negative charges
C)
contain a positively charged, dense center
D)
contain a negatively charged, dense center
Answer:
c
Explanation:
I just learned all this in chemistry too lol
got 100 on the test last week so its good
Experiments with gold foil indicated that atoms contain a positively charged, dense center and the correct option is option C.
Experiments with gold foil, known as the Rutherford gold foil experiment, were conducted by Ernest Rutherford in 1911. In this experiment, he bombarded a thin gold foil with alpha particles.
Most of the alpha particles passed through the foil with little deflection, but some of them were deflected at large angles, and a small fraction even bounced back. This observation led Rutherford to conclude that the atom contains a positively charged, dense center called the nucleus, where most of its mass is concentrated. He proposed the nuclear model of the atom, which became a significant advancement in the understanding of atomic structure.
Thus, the ideal selection is option C.
Learn more about Gold foil experiment, here:
https://brainly.com/question/33537458
#SPJ6
The density of lead is 11.4g/cm3. What volume, in ft3, would be occupied by 10.0 g of lead?
Answer:
The volume is 3.09 ft^3.
Explanation:
The formula for volume is mass divided by density. 10.0 g / 11.4 g/cm^3 = 0.87719. Converted to cubis foot is 3.09 ft^3. I hope this helps you.
compare the size of F- and Na+ with atomic size of Neon?
Fluorine's atomic configuration is (2,7). As it's charge is -1, it will have 8 electrons in it's outermost shell thus filling its octate. similarly, Sodium loses one electron.
There you go :)
helpppppp i hate chemistry
I will give brainiest who helps me with the correct answer
I promise
5. Name the compound which contain Strontium, Fluorine, and Oxygen.
Options:
Strontium fluorate
Strontium fluoride
Strontium chlorate
Strontium fluorine
Answer:
The first option: Strontium Fluorate.
Explanation:
because Fluorine and oxygen combines to make fluorate, Strontium stays the same.
p.s: i need help in geo and there's an exam tomorrow.
Is vacuole a plant or animals cell
Answer:
plant
Explanation:
let me know if correct
What is the K-T boundary?
Answer:
Definition
The Cretaceous/Tertiary boundary (KT), also often called the Cretaceous/Paleogene (K/Pg) boundary, marks the contact between the Mesozoic and Cenozoic eras ∼ 65 Ma ago. The KT boundary is characterized by the last major mass extinction in Earth history that saw the demise of the non-avian dinosaurs along with 50% to 60% of the Earth fauna and flora.
Match the term (Endothermic) with the correct definition
energy goes into the chemical and cool downs the surrounding area.
energy leaves the chemical and cools down the surrounding area
energy leaves the chemical and heats up the surrounding area
Answer:
energy goes into the chemical and cool downs the surrounding area.
After pollen grows on a tube down the style,___
Answer:
as soon as the pollen reaches the stigma after the pollen grain descends down the style when the pollen tube grows into the ovule when the seed germinates
Explanation:
Express in scientific notation. Choose the answer with the proper number of significant figures. 9x10^9/4.5x10^1
Answer:
Your answer should be 2.4 x 10^9. please hit the crown
Explanation:
Which of the following sets of forces acting on an object will result in the object moving?
5 Newtons Up and 5 Newtons Down
31 Newtons Left and 32 Newtons Right
0 Newtons Up and 0 Newtons Down
9 Newtons Left and 9 Newtons Right
Answer:
31 N left and 32 N right because
Explanation:
It’s the only one movement because when you subtract them there’s still 1 left
Which of these is an example of chemical separation of a substance?
-Distillation
-Magnetism
-Paper Chromatography
-Bond breaking
Answer:
Bond broking
Explanation:
Bond broking.
A state property X has a value 89.6 units. It undergoes the following changes, first increase by
3.6 units, then increase by another 18.7 units, then decrease by 12.2 units and finally attains a
value of 85.5 units The value for this series of change is A) 14.2 units
B) -4.1 units C) 108.3 units
D) uncertain
Answer:
B) -4.1 units
Explanation:
According to this question, a state property X has a value 89.6 units. It undergoes the certain changes as follows:
- first increase by 3.6 units
- then increase by another 18.7 units
- then decrease by 12.2 units
- and finally attains a value of 85.5 units
This can be mathematically represented by 89.6 - {3.6 + 18.7 - 12.2 - x) = 85.5
To get x, we say;
89.6 + 3.6 = 93.2
93.2 + 18.7 = 111.9
111.9 - 12.2 = 99.7
99.7 - 85.5 = 14.2units.
The changes that occured is represented as follows:
= (3.6 + 18.7) - (12.2 + 14.2)
= 22.3 - 26.4
= -4.1 units
how do i caculate velocity
Answer:
Velocity Equation in these calculations:
Final velocity (v) of an object equals initial velocity (u) of that object plus acceleration (a) of the object times the elapsed time (t) from u to v.
Explanation:
If the momentum of a car is reduced by half, assuming mass did not change, what must also have been reduced by half?
Answer:
Velocity is halved
Explanation:
Momentum is contingent on mass and velocity. The quantity of motion in a body is called the momentum of the body.
Momentum = mass x velocity
Now, if mass does not change and momentum is reduced by half, it suggests that the velocity was reduced by half.
Velocity is directly related to momentum.
Niels Bohr’s model of the atom helped to explain
Answer:
a theory for the hydrogen atom based on quantum theory that energy is transferred only in certain well defined quantities. Electrons should move around the nucleus but only in prescribed orbits.
Explanation:
Please help me how do i solve this
Answer:120
Explanation:2gfdxxfgngfnf