Which of the following is considered a sign of a chemical change?
Through which material does light move fastest?
Answer:
Explain that unlike sound, light waves travel fastest through a vacuum and air, and slower through other materials such as glass or water.
Explanation:
Hope this helped.
Answer:
empty space
Explanation:
which of these is an element?
KBr
O2
2KCl
FeO2
Answer:
02
Explanation:
all the other options given are compounds
change word equation into chemical equation.
a Calcium carbonate -----> Calcium oxide + Carbon dioxide
b Zinc + Sulphuric acid -----> Zinc sulphate + Hydrogen
Answer:
Ca(CO3) --> CaO + CO2
Zn + H2SO4 --> ZnSO4 + 2H2
Explanation:
^^^
PLEASE HURRY (WILL MARK BRAINLIEST)
What happens when the sound waves released by a bat hit an object?
The sound waves are diffused.
The sound waves are reflected.
The sound waves are refracted.
The sound waves are absorbed,
Answer:
B.) The sound waves are reflected.
Explanation:
On edge,
i also answered so the other person could get the brainliest
Answer:
b
Explanation:
What physical property of the metal rods was being tested during step 4 of the procudure?
4. Measure and record how long it takes heat from the hot plate set on "high" to melt the wax ball.
A.
magnetism
B.
thermal conductivity
C.
electrical conductivity
D.
density
Answer:
B. thermal conductivity
Explanation:
They physical property being tested during the fourth step is the thermal conductivity of the materials.
Thermal conductivity is the ability of a body to transmit heat energy from one place to another.
Since we are measuring how long it takes for heat from the hot plate to reach the wax ball, this is a typical experiment for measuring thermal conductivity. Most metals are good conductors and heat energy moves fast in them.Non-metals are poor conductors with low thermal conductivity.How is heat transferred when you touch an ice cube?
Answer:
The heat is transferred from your hand to the ice, this is because, as we know, heat gets transferred from a hot object to a colder object.
In this case, our hand is clearly hotter than the ice cube.
Therefore, the heat is transferred from your hand to the ice cube.
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Plz help! The best answer will be marked as brainliest!
Make a funny sentence for the beneficial or great uses of magnesium
I DON¨T WANT A MEME!
Here is an example for Mercury, it HAS to for Magnesium
¨I have a long history of use in fluorescent lighting so I can light up any room ¨
Answer:
"Like when people say like im a party fowl but I'm like OMg, I'm like the reason everyone loves the 4th of July like I am 4th of July.
Explanation:
As magnesium ignites easily in air and burns with a bright light, it's used in flares, fireworks and sparklers. I imagine Magnesium talks like a valley girl lol.
A piece of gold has a mass of 21.7 kg and a volume of 5.78 cm3 . What is the density of gold? (Convert kgg)
Answer:
The answer is 3754.33 g/cm³Explanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
From the question
mass = 21.7 kg = 21700 g
volume = 5.78 cm³
We have
[tex]density = \frac{21700}{5.78} \\ = 3754.3252...[/tex]
We have the final answer as
3754.33 g/cm³Hope this helps you
In a solution, the particles of different substances are ___ a. mixed evenly, b. never mixed, c. mixed unevenly, d. separated from each other. PLEASE ANSWER ASAP TY
Select the molecular shape of each molecule based on the formula or Lewis structure.
Answer:
1. linear (A)
2. trigonal-planar (C)
3. tetrahedral (B)
4. linear (A)
Explanation:
Just did it on Edge 2020
The shape of a molecule can be predicted from the number of electron pairs that surround the central atom in the molecule.
The Valence Shell Electron Pair repulsion theory gives us a basis for predicting the shape of molecules. The shape of a molecule can be predicted from the number of electron pairs that surround the central atom in the molecule.
In the image shown, We can see that in HCN , carbon is the central atom and is surrounded by two atoms and no lone pairs. Since there are two electron domains around the central atom, the molecule is linear.
In the second structure, BH3 has boron as its central atom. Three electron domains surround the central atom hence the molecule is trigonal planar.
Learn more: https://brainly.com/question/25249351
Which of these reactants will produce a precipitate if they react?
NaC2H3O2+ HCI
NaOH + HCI
NaNO3 + CaCl2
KOH + Mg(NO3)2
Answer:
KOH+Mg(NO3)2
Explanation:
The double replacement reaction will result in:
2KOH(aq) + Mg(NO3)2[tex]\\[/tex](aq)--> 2KNO3(aq) + Mg(OH)2(s)
Solubility rules prove that Mg+OH^- is insoluble and will result in a precipitate (solid)
Determine the mass of 31.4 moles of Sodium.
Answer:
721.9 grams
I hope this helps!
Plz help! I’m on a timer!
Answer: c. ceabd
Explanation: Substances that are more dense move to the bottom of the beaker. Substances that are less dense float to the top.
HURRY PLS!
A wave has a wavelength of 915 meters. what is the frequency of the light?
Answer:
327.8689 (Hz)
0.3279 (KHz)
0.0003 (MHz
0 (GHz)
What happens to the atomic radius when an electron is lost?
A. The positive ionic radius is the same size as the neutral atomic
radius.
B. The positive ionic radius does not follow a trend with the neutral
radius.
C. The positive ionic radius is smaller than the neutral atomic radius.
D. The positive ionic radius is larger than the neutral atomic radius.
Answer:the positive ionic radius is smaller than the neutral atomic radius
Explanation:
Answer:The positive ionic radius is smaller than the neutral atomic radius.
Explanation: just took the test
4. Advection fog forms when warm moist air comes in from the Pacific Ocean and
blows over the cold California current.
A.True
B.False
Answer:
A, True
Explanation:
Explain why the mass number of oxygen is 16
Answer:
Oxygen has an atomic number of 8 , and the mass number of an atom is the sum of its atomic number plus its neutron number. We got the mass as 16 units, and so it'll have 16−8=8 neutrons.
Explanation:
A sample of N2H4 has a mass of 25g. Identify the numerical quantity that is needed to convert the number of grams of N2H4 to the number of moles of N2H4. (You do not need to do the actual calculation.)
Answer:
Molecular Mass
Explanation:
It's asking for the numerical quantity. That quantity would be the Molecular Mass. Take the sample mass and divide it by the molecular mass to get the number of moles.
(14g N * 2) + (1g H *4) = 32g / mol of N2H4
To get # of moles, divide the sample mass by the molecular mass
25g / 32g = 0.78125 moles
a cylindrical object has a diameter of 1.25 cm and a height of 6.48 cm. what is its volume?
The volume of cylinder = 7.948 cm³
Further explanation
Volume is a derivative quantity derived from the length of the principal
The unit of volume can be expressed in liters or milliliters or cubic meters
The volume of the aquarium is almost the same as the beam namely:
V = length x width x height
The volume of a cylinder can be formulated :
[tex]\tt V=\pi.r^2.h[/tex]
r = radius
h = height
radiusDiameter of cylinder = 1.25 cm
radius=r :
[tex]\tt \dfrac{1.25}{2}=0.625~cm[/tex]
volume[tex]\tt V=\pi\times 0.625^2\times 6.48\\\\V=\boxed{\bold{7.948~cm^3}}[/tex]
Balance the following chemical equations
Answer:
1) 3Fe + 2O(2, this is the subscript) - Fe(3)O(4)
2) 2Sr + O(2) - 2SrO
3) Sn + 2NaOH - Na(2)SnO(2) + H(2)
4) 2K + Br(2) -2KBr
5) 2C(8)H(18) + 25O(2) - 16CO(2) + 18H(2)O
use the facts that water has a higher specific heat than rock (such as Granite) to explain the differences in the temperature curves for the two cities in the graph.
Since water has a high specific heat, that results in water being able to store/require more energy in order to change it’s temperature. Since San Francisco is so close to water, that would mean that it’s temperature should vary less since water would be able to keep the temperature around the same value even if there was an increase or decrease in thermal energy.
How many joules of heat are absorbed when 70.0 grams of water is completely vaporized at its boiling point ?
Answer: The answer would be 158,200
How many moles of gold, a U, are in 3.60×10^-5 G of gold?
Answer:
See Below.
Explanation:
This is a conversion problem:
Using the molar mass of Gold (given in a periodic table) which is 196.97g/mol
you have
[tex](3.60*10^-5 g) *\frac{1moles}{196.97g}[/tex]
you always arrange the equation in a way to cancel whatever you don't want (grams) and leave what you do want (moles). Here grams cancel (top and bottom), so you're left with:
[tex]\frac{(3.60*10^-5 g) *(1)}{196.97} = 1.83*10^-7[/tex] moles of Gold
How many miles are there in 12327 feet
Explanation:
2.3346591 miles is in 12327 feet
Answer:
2.3346591Explanation:
Always remember, to convert
feet to miles, all you have to do is
divide the length by 5280 and then
you will get this much miles: 2.3346591
Hope this helps! <3
What type of heat transfer happens in the Inner Core?
Answer: Conduction
Explanation:
Calculate the number of moles of neon gas in 8.15 x 10^24 atoms of neon gas.
1.35 moles Ne
0.135 moles Ne
135 moles Ne
13.5 moles Ne
Answer:
13.5 moles of Ne
Explanation:
1 mole of any gas contains 6.02 x 10²³ atoms of gas
6.02 x 10²³ atoms of neon is equal to 1 mole of neon .
8.15 x 10²⁴ atoms of neon is equal to 1 x 8.15 x 10²⁴ / 6.02 x 10²³ moles
= 8.15 x 10²⁴ / 6.02 x 10²³ mole o neon
= 13.5 moles of Ne .
HELP ME ASAP PLEASE IDK THIS
Answer:
cExplanation:
How many d electrons does I (atomic number
53) possess?
1. 10
2. 5
3. 8
4. 0
5. 20
6. 53
7. 16
Answer:
6. 53 is the answer. Hope this helps:)
The number of d electrons that an atom of atomic number 53 possess are 20. Thus, the correct option for this question is 5.
What is an Atomic number?An atomic number may be defined as the number of protons in the nucleus of an atom that significantly represents the characteristic of a chemical element and determines its specific place in the modern periodic table.
According to the modern periodic table, an element that has an atomic number of 53 is known as Iodine. Its electronic configuration is [tex]1s^2, 2s^2, 2p^6, 3s^2, 3p^6, 4s^2, 3d^1^0, 4p^6, 5s^2, 4d^1^0, 5p^5[/tex]. Thus, according to this electronic configuration, the total number of d electrons are [tex]3d^1^0 and 4d^1^0[/tex].
Therefore, the number of d electrons that an atom of atomic number 53 possess are 20. Thus, the correct option for this question is 5.
To learn more about Electronic configuration, refer to the link:
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How many significant figures does this measurement contain? 0.0000508800 Gm
Answer:
There are 6 significant figures
Answer:
6 significant figures
Explanation:
When counting significant figures, start on the left with the first non-zero number. Count all numbers that fall between non-zero numbers. Count all zeros after a 1-9 and after the decimal.