Answer:
lava
Explanation:
can copper be scratched by a fingernail or blade knife. why?
Answer:
it could by blade knife
Explanation:
fingernail has hardness 2.5; copper penny, about 3.5; a knife blade, 5.5
How many minutes will it take to plate out 4.50 g of Cu from a solution of Cu(NO3)2 (aq) onto the cathode of an electrolytic cell when 8.00 A of current are used?
a. 28.5 min.b. 3.06 × 10^−9 min.c. 14.2 min.d. 1.82 × 10^3 min.
Answer:
a. 28.5 min
Explanation:
The computation of the number of minutes would it take to plate out is as follows:
Cu+2 +2e [tex]\rightarrow[/tex]Cu
The two moles of electrons could be generated for the copper i.e. deposited
Now
moles of copper is
= 4.5 ÷ 63.5
= 0.071
The 63.5 represents the atomic copper weight
Now mole of electrons deposited is
= 0.071 × 2
= 0.142
Now
quantitiy of electricity needed
= moles of electrons deposited × 96500
= 0.142 × 96500
= 13703 coulums
As per electricity quantity needed
= current × time(seconds)
= 13703 = 8 × t
t = 13703 ÷ 8
= 1713 seconds
= 1713 ÷ 60 minutes
=28.5 min
hence, the correct option is a.
CAN YOU PLZ HELP ME ITS TIMED BRAINLIEST!
ONLY ANSWER IF YOU KNOW THE ANSWER PLZ!
The diagram shows two chromosomes paired up.
Which process is being shown?
sexual reproduction
independent assortment
crossing over
chromosome separation
Answer:
the sexual reproduction
Explanation:
Which of the following is an example of potential energy? O A. The energy of vibrating air O B. The energy of moving particles O C. The energy in chemical bonds OD. The energy of a runner on a flat road
D
Explanation:
i hope so it is the answer
In metallic bonding, the electrons A. are unable to move. B. are shared between two single atoms. C. are given to one atom by another atom. D. are in a "sea" around the protons of all the metal atoms.
Answer: I think it’s A.
Explanation:
Tell me if it’s wrong sorry, I am only in middle school level science.
True or False
ATP energy is used to move muscles and build protein in your body
which formula represents a nonpolar molecule containing polar covelant bond
Answer: H2O and NH3 are polar molecules. H2 is a nonpolar molecule but the H-H bond is also nonpolar.
Therefore, the best choice is CCl4. Although the C-Cl bond is polar due to electronegativity differences, the molecule itself is nonpolar because the net dipole moments cancel out, given its tetrahedral molecular structure.
Explanation:
A complex absorbs photons with an energy of 4.10×10^−19 J. What is the wavelength of these photons? If this is the only place in the visible spectrum where the complex absorbs light, what color would you expect the complex to be?
Answer:
483 nm corresponds to blue light hence the complex will appear orange.
Explanation:
Using the formula;
E= hc/λ
Where;
E = energy of the photon
h = Plank's constant (6.6*10^-34Js)
c = Speed of light (3*10^8 ms-1)
λ = wavelength
λ = hc/E
λ = 6.6*10^-34 * 3*10^8/4.10×10^−19
λ = 4.83 * 10^-7 or 483 nm
483 nm corresponds to blue light
Using the colour wheel approach, if a complex absorbs blue light, then it will appear orange.
In the reaction __S+3O2→2SO3, what coefficient should be placed in front of the S to balance the reaction?
Question 1 options:
1
2
3
Answer:
2
Explanation:
because on the product side you have 2 sulfurs so you need 2 on the reactant side.
What is the mass of 1.00 mol of oxygen (O2)?
Answer:
Mass = 32 g
Explanation:
Given data:
Number of moles of oxygen = 1.0 mol
Mass of oxygen = ?
Solution:
Formula:
Number of moles = mass/molar mass
Molar mass of oxygen (O₂) is 32 g/mol
by putting values,
1.0 mol = mass/ 32 g/mol
Mass = 1.0 mol ×32 g/mol
Mass = 32 g
what are 4 sources of electrical energy?
Answer:
Clean Energy. Learn more about energy from solar, wind, water, geothermal, biomass and nuclear. Fossil. Learn more about our fossil energy sources: coal, oil and natural gas.Electric Power. Learn more about how we use electricity as an energy source. Energy Storage. Hydrogen & Fuel Cells.Explanation:
I hope this helps xD
Answer:
Electrical energy is used to power up a light bulb. The current moves from the outlet to the light bulb through the wire.
Lightning is another example of electrical energy. The negatively charged particles are separated from the positively...
Batteries are also sources of electrical energy. In car batteries, the moving charges Explanation:
fI gave u 3 think of the 4th one
balance the chemical equation KC1O3→KC1+O2
Answer:
2 KCO3 → 2 KC + 3 O2
Explanation:
Reaction Type
Decomposition
Reactants
KCO3
Products
KC
Dioxygen - O2
O₂ Oxygen Molecular Oxygen Diatomic Oxygen Triplet Oxygen Oxygen Gas Liquid Oxygen LOx
NEED HELP ASAP!!! I just need to know the order
Atom and Periodic table vocabulary:
1. The mass on the periodic table.
2. Particles that differ in number between isotopes.
3. Vertical column in the periodic table.
4. Atoms of the same element that have different masses.
5. All elements in the same one of these has the same number of energy levels in their electron cloud.
6. The smallest form of matter that still retains the properties of an element.
key:
Neutrons
Quark
Average atomic mass
Isotopes
Group
Period
Answer:
1. The mass on the periodic table.
Average atomic mass
2. Particles that differ in number between isotopes.
Neutrons
3. Vertical column in the periodic table.
Group
4. Atoms of the same element that have different masses.
Isotopes
5. All elements in the same one of these has the same number of energy levels in their electron cloud.
Period
6. The smallest form of matter that still retains the properties of an element.
Quark
Explanation:
HELP!!
IF YOU DON'T KNOW THE ANSWER DON'T ANSWER!
Answer: increase
Explanation:
ahhhhhhhhhhhhhhh
Which is a component of John Dalton’s atomic theory?
The ratio of atoms in a compound is fixed.
The atoms of different elements are the same.
An atom is a small particle of matter that can be broken down.
A reaction can create or destroy atoms as well as rearrange them.
Answer:
i think the answer is b
Explanation:
Please help with this question..thank you
) How many moles are there in 2.00 x 10^19 molecules of calcium phosphate?
Answer:
[tex] \huge 3.322 \times {10}^{ - 5} \: \: moles \\ [/tex]
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{2.00 \times {10}^{19} }{6.02 \times {10}^{23} } \\ \\ = 3.322 \times {10}^{ - 5} \: \: moles[/tex]
Hope this helps you
Calculate the amount of heat, in Joules, needed to raise 34.0g of water from 55.0°C to 76.0*C. The specific heat of water is 4.18 J/gºC.
Answer:
2984.52J
Explanation:
Using the formula: Q = m × c × ∆T
Where;
Q = amount of heat (in Joules)
m = mass (in grams)
c = specific heat capacity (J/g°C)
∆T = change in temperature (°C)
Based on the information provided in the question;
m = 34.0g
c = 4.18 J/gºC.
Initial temperature = 55.0°C
Final temperature = 76.0°C
Hence, Q = m × c × ∆T
Q = 34 × 4.18 × (76 - 55)
Q = 142.12 × 21
Q = 2984.52J
Therefore, 2984.52J is the amount of heat, in Joules, needed to raise 34.0g of the water.
Your aunt is sipping on iced tea and fanning herself during a hot South Carolina summer day. You tell her that there is enough energy in one drop of her iced tea to run the air conditioner for the rest of her life if the energy could be extracted with 100% efficiency. Your aunt asks you to explain. Use the concepts you learned in this unit to explain the relationship between forces, energy, and matter.
Answer:
Isn't this like having enough energy to supply the world for centuries with just 1% of the sea's force?
Explanation:
I guess it's because the amount of energy in it can supply energy.
What is the atomic radius
Answer:
The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding shells of electrons.
Help lol please lol thank you :)
Answer:
45
Explanation:
Answer:
45 lol
Explanation:
What is an nucleus ?
Nucleus is present at the centre of atom. It contains protons and neutrons. It is very small as compared to the atom.
Answer:
It is a part of a cell which controls all the activities in the cells and contains the genetic information of the cell that is to be passed down to the next cell when it reproduces.
Explanation:
It is a part of a cell which controls all the activities in the cells and contains the genetic information of the cell that is to be passed down to the next cell when it reproduces.
17 Which changes decrease the rate of reaction between magnesium and air?
1.heating the magnesium to a higher temperature
2.using a higher proportion of oxygen in the air
3.using magnesium ribbon instead of powdered magnesium
A 1, 2 and 3
B 1 only
C 2 only
D 3 only
Using magnesium ribbon instead of powdered magnesium decrease the rate of reaction between magnesium and air.
What is rate of reaction?Rate of reaction tells about the duration of the completion of the reaction.
Rate of any reaction is directly proportional to the concentration and surface area of the reactant, temperature, catalyst, no. of collision, activation energy, etc.
So, if we magnesium in the ribbon instead of powdered magnesium the surface area of the reactant side decreases which results in the decrease of the rate of reaction.
Hence, option (D) is correct i.e. rate of reaction decreases on using magnesium ribbon instead of powdered magnesium.
To know more about rate of reaction, visit the below link:
https://brainly.com/question/1898560
Adaleigh is learning about renewable and non-renewable resources in her science class. She decides to take
a nature walk and makes notes of all the renewable resources that she sees. Which of the following is an
observation that Adaleigh could have made on her walk?
A. The seeds on the ground are going to grow into new trees.
B. The tallest trees had the most seeds around their bases.
C. When trees decay, they could eventually turn into coal.
D. Pine trees are older than oak trees.
Answer:
A. The seeds on the ground are going to grow into new trees.
Explanation:
Trees are renewable resources.
When circumstances are right, most materials undergo a process called thermal expansion. Which statement best describes the cause and effect of thermal expansion? Group of answer choices Matter is heated, and its particles spread out more. Matter is heated, and its particles move closer together. Matter is cooled, and its particles move closer together. Matter is cooled, and its particles spread out more.
Answer: Matter is heated, and its particles spread out more
Explanation:
Thermal expansion occurs when there's an expansion of an object or material or when an object becomes bigger because of a rise in its temperature. This brings about the faster movement of the heated molecules and the atoms spreading out.
Therefore, the cause and effect of thermal expansion will be that when matter is heated, and its particles spread out more.
A chemist combine did 3.50g of potassium level with chlorine gas to yield 6.6 7g of potassium for it. Assuming all the potassium was consumed, and that potassium chloride was the only product that formed, what mass of chlorine reacted?
Answer: mass of chlorine reacted is 3.18 g
Explanation:
2 K + Cl2 = 2KCl
no. of moles of K = mass / molar mass
= 3.50 / 39
= 0.0897
no. of moles of KCl = mass / molar mass
= 6.67 / 74.5
= 0.0895
no. of moles of Cl2 required = number of moles of KCl / 2
= 0.0895 / 2
= 0.0448 moles
mass of Cl2 required = no. of moles of Cl2 required x molar mass
= 0.0448 x 71
= 3.1808 g ≈ 3.18 g
Therefore mass of chlorine reacted is 3.18 g
Based on periodic trends which atom has a larger ionization energy then calcium Ca?
Answer:
Gallium, Germanium, Arsenic, Selenium, Bromine and Krypton
Explanation:
Based on periodic trends, the atom that has a larger ionization energy than calcium are Gallium, Germanium, Arsenic, Selenium, Bromine and Krypton.
Across the period, the ionization energy increases from left to right.
Ionization energy is the energy required to remove the most loosely held electron within an atom. As you go from left to right, the ionization energy increases rapidly.The elements to the right of Ca will have a higher ionization energy compared to Ca.When [H+] = 4.0 × 10–9 M in water at 25°C, then
Kw =1.0×10–14.
b. pOH = 7.
c. [H3O+] = [OH–].
d. pH= 7
e. A-D are all correct
Answer:
a. Kw = 1.0 × 10⁻¹⁴
Explanation:
a. Let's consider the self-ionization of water.
2 H₂O(l) ⇄ H₃O⁺(aq) + OH⁻
The ion-product of water (Kw) at 25 °C is:
Kw = [H₃O⁺][OH⁻] = 1.0 × 10⁻¹⁴
c. Considering [H⁺] = [H₃O⁺] = 4.0 × 10⁻⁹ M, the concentration of OH⁻ is:
[OH⁻] = 1.0 × 10⁻¹⁴/[H₃O⁺] = 2.5 × 10⁻⁶ M
b. We can calculate the pOH using the following expression.
pOH = -log [OH⁻] = -log 2.5 × 10⁻⁶ = 5.6
d. We can calculate the pH using the following expression.
pH = -log [H⁺] = -log 4.0 × 10⁻⁹ = 8.4
When [H+] = 4.0 × 10–9 M in water at 25°C, then the [tex]Kw =1.0\times 10^-^1^4.[/tex]
What is dissociation constant?
Kw is the dissociation constant or ionization constant of water.
The self-ionization of water will be
[tex]\rm 2 H_2O(l) = H_3O^+(aq) + OH^-[/tex]
The dissociation constant of the water at 25°C will be
[tex]\rm Kw = [H_3O^+][OH^-] = 1.0 \times 10^-^1^4[/tex]
Thus, the correct option is a. [tex]Kw =1.0\times 10^-^1^4.[/tex]
Learn more about dissociation constant
https://brainly.com/question/3657057
What pH scale number represents a neutral.
What pH scale number represents a neutral.
The answer is 7
