Answer:
10. D
9. A
8. A or B
Explanation:
10. Calcium has 20 electrons, but the Calcium ion has 18 electrons.
9. The mass of electrons are negligible.
8. Electrons have a very small mass where some consider it to have no mass.
Dec
Match each concept to the scientist who supported it.
Isaac Newton
Heinrich Hertz
Light is a wave because this property can
explain interference
Light is a wave because it bends when it
hits barriers and openings.
Light is made of particles because it travels
only in straight paths
Light is a wave made of electric and
magnetic fields
Light is a wave that has similar properties
James Clerk Maxwell
Christiaan Huygens
Thomas Young
as radio waves
Answer:the pic
Explanation:
Which step of the scientific method will most likely come next? Analyze the data Construct a hypothesis Test with an experiment Do background research
Answer:
analyze data and construct a conclusion
Explanation:
SOLVE A 4.80-gram piece of magnesium displaces 2.76 mL of water when it is placed in a graduated cylinder. What is the density of magnesium?
Answer:
Density = 1.74 gm/mL
Explanation:
Given that:
Mass of piece of Magnesium = 4.80 grams
The volume displaced by this piece = 2.76mL
Let us learn about a property:
Volume of water displaced by a substance when immersed in the water is equal to the Volume of the substance itself.
So, volume of the piece of Magnesium = 2.76 mL
To find:
Density of magnesium = ?
Solution:
Let us have a look at the formula for Density of a Substance:
Density of a substance is given as the ratio of mass of substance and the volume of that mass of substance.
i.e.
[tex]Density = \dfrac{Mass}{Volume}[/tex]
Putting the given values:
[tex]Density = \dfrac{4.80}{2.76}\\\Rightarrow \bold{Density = 1.74\ gm/mL}[/tex]
So, the answer is:
Density of Magnesium = 1.74 gm/mL
Mr block student are studying chemical
Answer:
egg
Explanation:
man
Portland cement concrete (PCC) has a density of 150 lb/ft3. How many kilograms of PCC are required to cast a cylindrical column 1.15 m in diameter and 7.8 m in height? (1 kg = 2.205 lb, 1 inch = 2.54 cm)
Answer:
Mass, m = 19466.7 kg
Explanation:
Given that,
Portland cement concrete (PCC) has a density of 150 lb/ft³
We need to find how many kilograms of PCC are required to cast a cylindrical column 1.15 m in diameter and 7.8 m in height.
Since, 1 kg = 2.205 lb
1 lb/ft³ = 16.018 kg/m³
150 lb/ft³ = 2402.77 kg/m³
Density, [tex]d=\dfrac{m}{V}[/tex]
m is mass of PCC in kg and V is volume of cylinder
[tex]m=d\times V[/tex]
[tex]m=d\times \pi r^2 h\\\\m=2402.77\times \pi \times (1.15/2)^2\times 7.8\\\\m=19466.70\ kg[/tex]
So, the mass of PCC required is 19466.7 kg.
Isotopes of an element have the same number of protons but different numbers of what?
I have no idea what subject to put this under qwq
Answer:
Isotopes is a phenomenon whereby atoms of the same element exhibit different mass numbers but have the same atomic number.I hope this helps... Thank you for the question
When water ionizes, it produces equal amounts of hydrogen and hydroxide ions that can reassociation with each other. The pH of water is:
Answer:
Explanation:
ionic product of water Kw = 10⁻¹⁴
[H⁺] [ OH⁻ ] = 10⁻¹⁴
[H⁺] ² = 10⁻¹⁴
[H⁺] = 10⁻⁷
Water dissociates as follows .
H₂O ⇄ H⁺ + OH⁻
10⁻⁷M 10⁻⁷ M
pH = - log [H⁺]
= - log [ 10⁻⁷ ]
= 7 .
So pH of pure water solution = 7 .
The pH of pure water is 7, which is considered neutral because it is neither acidic nor alkaline.
Determining the pH of waterWhen pure water ionizes, it produces equal amounts of hydrogen ions (H+) and hydroxide ions (OH-), according to the equation:
H2O ⇌ H+ + OH-
However, the concentration of H+ and OH- ions in pure water is very low, and the product of their concentrations is always equal to a fixed value at a given temperature. This value is 1 x [tex]10^-14[/tex] at 25°C.
The pH of water is a measure of its acidity or alkalinity, and is defined as the negative logarithm base 10 of the hydrogen ion concentration.
In pure water at 25°C, the hydrogen ion concentration is equal to the hydroxide ion concentration, and both are equal to 1 x [tex]10^-7[/tex] moles per liter.
Therefore, the pH of pure water at 25°C is:
pH = -log[H+]
= -log[1 x [tex]10^-7[/tex]]
= 7
Thus, the pH of pure water is 7, which is considered neutral because it is neither acidic nor alkaline.
Learn more on pH on https://brainly.com/question/12609985
#SPJ6
13) 2.4 L to mL
This is for chemistry
Answer: 2400 milliters
Explanation:
A chemist compresses a 1.8 L sample of carbon dioxide gas at 2.4 atm to a final volume of 1.5 L. Assuming the temperature is constant,what is the final pressure,in arm,exerted by the gas
Answer:
THE PRESSURE EXERTED BY THE GAS IS THEREFORE 2.88 atm.
Explanation:
Boyle's law states that at constant temperature, the volume of a given mass of gas is inversely proportional to the pressure of the gas.
Mathematically, P1 V1 = P2 V2
Write out the values of the variables given:
P1 = 2.4 atm
V1 = 1.8 L
V2 = 1.5 L
P2 = unknown
Re-arranging the variables by making P2 the subject of the equation, we have:
P2 = P1 V1 / V2
P2 = 2.4 * 1.8 / 1.5
P2 = 2.9=88 atm
Hence, the pressure exerted by the gas is therefore 2.88 atm
Define and explain auto-ionization of water??? Explain please??
Answer:
Hey there!
Auto-ionization of water is an ionization reaction in pure water or in another aqueous solution, in which a water molecule, H2O, loses the nucleus of one of its hydrogen atoms to become a hydroxide ion, OH−.
Let me know if this helps :)
Answer:
in pure water, H2O molecules undergo a reaction in which two molecules react in such a way that one molecule give its H+ ion to other molecule and become a hydroxyl ion(OH-) and molecule which gain H+ ion become H3O+ ion.
Explanation:
H2O + H2O ⇄ ( H3O+) +( OH-)
given the volume of a cube is 75 cm3 and the mass is 15 grams what is the density
Answer:
Density = 0.2 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 cube = 15 g
volume = 75 cm³
Substitute the values into the above formula and solve for the density
That's
[tex]Density = \frac{15}{75} [/tex]Density = 0.2 g/cm³Hope this helps you
Abby fills a graduated cylinder with 3 mL of water. She then
drops a small rock into the cylinder, and the water level rises
to the 5 mL mark. What is the volume of the rock?
mL
Answer:
The volume of the rock is 2 mL
Explanation:
The level to which the graduated cylinder is filled with water by Abby = 3 mL
The level to which the graduated cylinder after the rock is dropped in = 5 mL
Therefore;
The volume of the rock = The level to which the graduated cylinder after the rock is dropped in - The level to which the graduated cylinder is filled with water by Abby
The volume of the rock = 5 mL - 3 mL = 2 mL
The volume of the rock = 2 mL.
describe in brief the process of extracting Petroleum from its reserve
Answer:
There are three steps to the Petroleum refining process; separation, modification, and treatment. It would be impossible to drive without gas or diesel fuel. Learn how we get petrol and crude oil and more about gasoline or oil refineries. What is Petroleum? Petroleum is a natural phenomenon.
Explanation:
Your chemistry lab partner is interested in studying how industrial chemicals can pollute the environment. What type of chemistry would you recommend to your lab partner and which courses should they take in order to study it? Explain your answer.
Answer:
I would recommend them becoming an Analytical Chemist because Analytical Chemists examine and identify various elements and compounds to find out the composition, structure, and nature of substances and they determine the concentration of chemical pollutants in soil, water,and air. I would recommend taking inorganic, organic, analytical, and physical chemistry as well as computer science, physics, and environmental science
The protocol for a given lab experiment specifies that you should prepare 100 mL of a 0.10 M (mol/L) aqueous solution of NaNO3. You use a tared balance to deliver a given mass of solid into a weighing boat. To which piece of laboratory glassware should you transfer the solid to finish preparing the solution
Answer:
It should be transferred to a Beaker to finish preparing the solution
Explanation:
NaNO₃ is sodium Nitrate. It is a salt that is soluble in water hence it's aqueous solution can be prepared by dissolving it in water.
A beaker is a laboratory glassware that is used for various functions; one of which includes the preparation of reagents or aqueous solutions of a compound. In the example narrated in the question, the measured NaNO₃ solid can be transferred to a 100 mL or 200 mL beaker and then added to it is the desired volume of water to make the solution 100 mL. This solution can then be stirred with a "glass rod"
A balloon is filled to a volume of 1.6 L at 278 K. The balloon is left outside overnight and the temperature has dropped to 253 K. What is the new volume?
Explanation:
Charles' law gives the relationship between the volume and the temperature of the gas. Mathematically,
Volume ∝ Temperature
i.e. [tex]\dfrac{V_1}{V_2}=\dfrac{T_1}{T_2}[/tex]
We have, V₁ = 1.6 L, T₁ = 278 K, T₂ = 253, V₂=?
[tex]V_2=\dfrac{V_1T_2}{T_1}\\\\V_2=\dfrac{1.6\times 253}{278}\\\\V_2=1.45\ L[/tex]
So, the new volume is 1.45 L.
is a toothpick a good model for showing the strength and brittleness of salt ?
Answer:
no a toothpick is stronger
Explanation:
i would not seem right
Based on the data provided, do the Super Snail Snacks work? Explain your answer
Answer: No
Explanation: The snacks did not work because the result of the snails either stayed the same, or decreased.
what happens when ethylene gas is passed through cold dilute alkaline kMnO4 solution
Answer:
it gives CH2OH-CH2OH(ethylene glycol +MnO2
Explanation:
The relative formula mass (M) of XCO, is 84
Relative atomic masses (A.): C = 12 O = 16
Calculate the relative atomic mass (A) of X.
Answer:
x = 56
relative atomic mass is 58.933
Explanation:
finding the relative molecular mass of x first...
x + (C ×1) + (O ×1) =84
x + (12 ×1) + ( 16 × 1) =84
x + 12 + 16 =84
collect like terms
x = 84-12+16
x= 56
now...
half of 56...
56÷2 =27
and 27 is the atomic number of cobalt...
so relative atomic mass of cobalt is 58.933.
Water flows over Niagara Falls at the average rate of 2,400,000 kg/s, and the average height of the falls is about 50 m. Knowing that the gravitational potential energy of falling water per second = mass (kg) × height (m) × gravity (9.8 m/s2), what is the power of Niagara Falls? How many 15 W LED light bulbs could it power?
Explanation:
It is given that,
Water flows over Niagara Falls at the average rate of 2,400,000 kg/s
The average height of the falls is 50 m
We need to find the power of Niagara Falls.
The gravitational potential energy of falling water is given by :
P = mgh
Power is rate of doing work i.e.
[tex]P=\dfrac{W}{t}\\\\P=\dfrac{mgh}{t}\\\\P=\dfrac{m}{t}\times gh[/tex]
We have, m/t = 2,400,000 kg/s
So,
[tex]P=2400000\times 9.8\times 50\\\\P=1.176\times 10^9\ W[/tex]
If the number of bulbs are n that could power 15 W LED, the,
[tex]n=\dfrac{1.176\times 10^9}{15}\\\\n=78400000\ \text{bulbs}[/tex]
Is Plutonium an element, compound, solution* or heterogeneous mixture.
Answer:
Its an element.
Explanation:
94 on the periodic table
Practicing Density Calculations: A 4.80 gram piece of magnesium displaces 2.76 mL of water when it’s placed in a graduated cylinder . What is the density of the magnesium?
Answer:
1.74 g/mL
Explanation:
Step 1: Given data
Mass of magnesium: 4.80 g
Volume of water displaced: 2.76 mL
Step 2: Calculate the volume of the piece of magnesium
The volume of the piece of magnesium is equal to the volume of water displaced in the graduated cylinder.
Step 3: Calculate the density of magnesium
The density of magnesium is equal to its mass divided by its volume.
ρ = m / V
ρ = 4.80 g / 2.76 mL
ρ = 1.74 g/mL
A student measures the mass of a 6.0 cm3 block of brown sugar to be 10.0 g. What is the density of the brown sugar?
Answer:
1.67g/cm3
Explanation:
The formula for density is [tex]d=\frac{m}{v}[/tex] . The m variable stands for mass and the v variable stands for volume.
The mass of the brown sugar is 10.0g and the volume is 6.0cm3, so we can plug those values into the equation.
[tex]d=\frac{10g}{6cm^{3} }[/tex]
[tex]d=1.67[/tex][tex]\frac{g}{cm^{3} }[/tex]
Rounded to 3 significant figures, the density of the block of brown sugar is 1.67 g/cm3. If the mass is in grams and the volume is in cm3, the unit for the final answer is [tex]\frac{g}{cm^{3} }[/tex] (grams per centimetres cubed).
Answer:
16g
Explanation:
If Maria winks exactly five times every minute and she sleeps exactly eight hours every day, how many times does Maria blink every day
Answer:
4800 times a day
Explanation: she blinks 300 times every hour and i times it by 16 as the hours everyday (24-8) so 300 x 16 equals 4800
Scientists in a lab are working with two different samples of the element mercury. They know that the different samples are different isotopes. Which property of the isotopes must be different?
Answer:
the mass number
Explanation:
Isotopes are numerous forms of one single element. In simple terms, atomic weights are different for the isotopes. Isotopes refer to the atoms that have the same number of protons but different neutron numbers. The physical properties of the isotopes vary because these properties also based on mass. These variations can be used to distinguish isotopes of an element from each other by applying methods such as fractional distillation and diffusion.
Answer:
The mass number (D) would be correct.
Explanation:
I really need someone to explain how to find the average atomic mass.... the gizmos was really confusing because they also had weighted mass.
Answer:
Option C. 52.057
Explanation:
The following data were obtained from the question:
Isotope >> Mass number > Percentage
A (Cr-50) > 50 >>>>>>>>>> 4.3
B (Cr-52) > 52 >>>>>>>>>> 83.8
C (Cr-53) > 53 >>>>>>>>>> 9.5
D (Cr-54) > 54 >>>>>>>>>> 2.4
Average atomic mass =?
The average atomic mass of chromium, Cr can be obtained as follow:
Average atomic mass = [(Mass of A × A%) /100] + [(Mass of B × B%) /100] + [(Mass of C × C%) /100] + [(Mass of D × D%) /100]
Atomic mass of Cr = [50×4.3)/100] + [52×83.8)/100] + [53×9.5)/100] + [54×2.4)/100]
= 2.15 + 43.576 + 5.035 + 1.296
Atomic mass of Cr = 52.057
Therefore, the atomic mass of chromium, Cr is 52.057
If on average you walk 1.20 meters every second, how long do
you walk in one hour?
Chemicals used in a laboratory investigation must be safely discarded. Which method is the safest way to dispose of chemicals at the conclusion of a laboratory activity
Answer:
Disposing of the discarded chemicals can be done by certain sfae methods mention as follows:
Explanation:
Most of the chemical wastes are dispose through the EHS waste program. Organic chemicals and solvents that can not be drain should be closed in a tight fitted container that has label on it as Hazardous waste, including strong acid and corrosive liquids.
Recycling of these chemicals and incineration is also use for the industrial chemical waste under professional guidance. Incineration is the process of burning chemicals in to ash through high thermal burning.
HELP PLZ!!! Which must be kept in mind when determining if an explanation is correct? whether people reading the explanation agree the information that is on the Internet that there may be more than one way to interpret data whether a person of authority says it is correct
Answer: C. that there may be more than one way to interpret data
Enge 2020 C is the correct answer