Answer:
Magnesium Oxide (MgO) has a higher melting point than Sodium Chloride (NaCl) which is around 2,800 degrees Celcius. This is because its Mg2+ and O2- ions have a greater number of charges, and so form stronger ionic bonds, than the Na+ and Cl– ions in Sodium Chloride.
10. How many molecules in this chemical equation?
3(OH)2 A 3, B 6, C 7, D 2
Answer:
B, 6
Explanation:
Which of the following is considered a sign of a chemical change?
11) Look at the phenotypes of Beyonce and
Jay Z. If these two had children, could they have
children with a widow's peak? Why or why not? Use
a Punnett Square to explain your answer.
Help me please
Answer:
No
Explanation: Neither has the dominant trait for Widow's peak, so they're both aa
A brief explanation to this question: "Why are neon signs/fireworks different colors? Please help me. Do not look up internet
Answer:
when lit, the atoms of different chemical compounds inside the firework absorb energy, when the electrons fall back to lower energy levels, they give off colored light. Depending upon the chemical used, different colors are produced. neon lights or signs are glass tubes filled with neon gas. When the light is plugged in, the electrical energy causes the electrons of neon to jump to higher energy levels, when they go to lower levels, colored light is given off. The neat thing is that the neon never gets used up. The only thing that gets used up is the electricity. The electrons don't get destroyed and can be used over and over again jumping levels. Neon glows with an orange light, but you know that neon signs can be lots of different colors. The variations come when different gases other than neon are used such as argon, or krypton or when the tube is painted so that with the light produced it produces a certain color.
Explanation:
After being excited by high levels of electrical energy (as in neon signs) or heat energy, various elements and molecules will emit their own specific colors of light.
What are basis behind fireworks?Metals burn in a variety of colors. When a copper compound is lit, for example, the flame is blue-green.
Calcium burns red, while potassium burns purple. Metals are combined to produce various colors in fireworks.
The appearance of each firework is determined by the type of stars it contains, as well as the size and quantity of these pellets.
Some stars contain metal salts, which produce brilliant colors, while others contain a variety of chemical compounds that produce dazzling light effects such as strobing, sparkling, and others.
Various elements and molecules will emit their own specific colors of light after being excited by high levels of electrical energy (as in neon signs) or heat energy (as in the fireworks).
Thus, the neon signs or fireworks provide different colors.
For more details regarding fireworks, visit:
https://brainly.com/question/16737516
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answer question in picture please.
Answer:
b
Explanation:
kkkk(kkkkkkkkkkkkwritten am an ah roo ero di si di dh dh ah ah eh si eri di do
Answer: the answer is B. C
Explanation:
Iron, a metal, has which of the following features?
electrons that transfer between atoms to make cations and anions
a sea of electrons
firmly bonded electrons
electrons shared between single pairs of atoms
Answer: A sea of electrons
Explanation:
Neodymium battery + sulfuric acid ——> neodymium sulfate + iron sulfate + boron + hydrogen. I have 5g of Nd2Fe14B and enough H2SO4, how much NdSO4 will I get?
Mass of Nd₂(SO₄)₃ : 2.653 g
Further explanationReaction
Nd₂Fe₁₄B + 17H₂SO₄ → Nd₂(SO₄)₃ + 14FeSO₄ + B + 17H₂
5 g Nd₂Fe₁₄B
MW = 2. 144,242 + 14. 55.845 + 10.811
MW = 288.484 + 781.83+10.811=1081.125 g/mol
mol :
[tex]\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{5}{1081.125}=0.0046[/tex]
mol Nd₂Fe₁₄B = mol Nd₂(SO₄)₃=0.0046
so mass of Nd₂(SO₄)₃ :
MW Nd₂(SO₄)₃ = 2.144.242+3.32,065+12.15,999
MW = 288.484+96.195+191.988=576.667 g/mol
[tex]\tt mass=mol\times MW\\\\mass=0.0046\times 576.667\\\\mass=2.653~g[/tex]
What is the total number of hydrogen atoms contained in one molecule of (NH4)2C204?
6
8
4
2
Answer:
=8 atoms
Explanation:
In (NH4)2C2O4 there are four moles of Hydrogen in the compound (NH4), but there two molecules of (NH4) in this compound. That's what the 2 in (NH4)2 means, so multiply 4 x 2 = 8.
Hope this helps (:
what is the factor that changes the reaction rate in the following example and why:
More concentrated detergents wash better.
Answer:
Concentration of the detergents
Explanation:
The factor that changes the reaction is the concentration of the reacting detergent.
Here are some factors that influences the rate of reaction;
Nature of reactantsConcentration of the reactants or pressure Temperature Presence of a catalystSunlightThe reaction rate is directly proportional to the concentration of the reactants.
Here since we have a more concentrated detergent, its reaction rate will be higher than normal and it will wash better.
1) the average rate of reaction in the first minute
2)the average rate of reaction in the second minute
3)the time when the reaction has completed
4)the average rate of reaction for overall reaction
5)the rate of reaction at 30 seconds
6)the rate of reaction at 105 seconds
1. 0+15+30+45+60=150/5=30 s
0+10+16+22+27=75/5=15 cm^3
then, 15/30= 0.5 cm^3/s(average rate of rxn)
2. 0+15+30+45+60+75+90+105+120=540/9=60 s
0+10+16+22+27+31.50+36+39.5+42=224/9=24.89cm^3
then, 24.89/60=0.414cm^3/s (avrg rate of rxn)
3. overall rxn add all the time divide by 12 and the volume add them too and divide by 12. after take average volume divide by the average time to get the average rate of overall rxn
4. 16/30= 0.533cm^3/s
5. 39.5/105= 0.37cm^3/s
A trucker is driving from New Jersey to California to make a delivery of couches. He forgets to adjust the pressure of his tires before his trip and end up blowing out two of his tires while driving through Arizona. Whose law does this example depict? What does this law state? Use the law to explain what happened to the tires.
Answer:
Gay-Lussac's law.
Explanation:
According to Gay-Lussac's pressure law, it states that the pressure of a given mass of gas is directly proportional to the absolute temperature of the gas, the assumption that the volume is kept constant.
Hence, the trucker's tires were blown up because they were under high pressure as he drove from New Jersey to California, as a result of this intense pressure the temperature of the air in the tires began to rise and it directly affected the pressure of the gas in the tires' tubes which also increased to a point that they ended up blowing out, obeying Gay-Lussac's law.
when two or more atoms are combined it is called a ?
Answer:
Elements can be chemically combined into compounds, therefore, a compound consists of two or more elements combined, in definite proportions, by chemical means. Compounds may be formed by combining atoms of their constituent elements by ionic bonds or by covalent bonds.
Which of the following has the smallest atomic radius?
A. Astatine
B. Bromine
C. Fluorine
D. Iodine
Answer:fluorine
Explanation:
Which of the following is a mineral?
coal
ling
glass
brick
salt
Mr. Knowlton loves to throw a football around for fun. In the
summer, he and his brothers bought a new ball that was in perfect
condition. However, in the winter they noticed that the ball was not
the same. It seemed to have less volume even though there were no
leaks in the ball! Why?
Will cardboard sink in cold or hot water faster
PLEASE HELP!!
A model stands on a scale and finds her weight to be 105 pounds. If
the pressure exerted by her feet on the scale is 2.16 pounds per
square inch, what is the area of her feet in cubic centimeters?
__cm2
Answer:
313.5cm²
Explanation:
Given parameters:
Weight of model = 105pounds
Pressure applied on the scale by model = 2.16pounds per square inch
Unknown:
Area of her feet in cm² = ?
Solution:
Pressure is the force per unit area;
Pressure = [tex]\frac{Force}{Area}[/tex]
Input the parameters and solve;
2.16 = [tex]\frac{105}{Area}[/tex]
105 = 2.16 x Area
Area = [tex]\frac{105}{2.16}[/tex] = 48.6in²
We need now to convert the in² to cm²
1in² = 6.45cm²
48.6in² = 48.6 x 6.45 = 313.5cm²
A 0.2027 gram sample of finely powdered limestone (mainly CaCO₃) was dissolved in 50 mL of 0.1035 M HCl. The solution was heated to expel CO₂ produced by the reaction. The remaining HCl was then titrated with 0.1018M of NaOH and it required 16.62 mL. Calculate the percentage of CaCO₃ in the limestone sample? CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O
Answer:
Explanation:
CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O
100 gm + 2000 mL of M HCl
Amount of HCl remaining = .1018 M of 16.62 mL
= .1018 x 16.62 mL of M HCl
= 1.69 mL of M HCl
Initial HCl taken = 50 mL of .1035 M HCl
= 5.175 mL of M HCl
HCl reacted = 5.175 - 1.69 mL of M HCl
= 3.485 mL of M HCl
2000 mL of M HCl reacts with 100 gm of CaCO₃
3.485 mL of M HCl will react with .174 grams of CaCO₃
percentage of calcium carbonate = .174 x 100 / .2027
= 85.84 %
What is the mass (g) of 6.50 moles of water (H2O)? While using moleconversion
Answer:
Mass = 117 g
Explanation:
Given data:
Moles of water = 6.50 mol
Mass in gram = ?
Solution:
Formula:
Number of moles = mass/molar mass
Molar mass of water = 18 g/mol
Now we will put the values in formula.
6.50 mol = mass/ 18 g/mol
Mass = 6.50 mol×18 g/mol
Mass = 117 g
3. Two boxes need to be moved. Box A is 10 kg. Box B is 3 kg. Which box will 1 point
require more force to move?
BOXA
BOX
Answer:
box A
Explanation:
10 is bigger than 3 since 10 is bigger it has more force in it
How much energy is required to heat 23 grams of iron from 1150 degrees celsius to 2000 degrees Celsius? The melting point of iron is 1538 degrees celsius and the specific heat capacity is 0.444 J/g*C when it is in a solid and 0.450 J/g* C when it is liquified. Latent heat of Fusion of iron is 13.8kj/mol and Latent Heat of Vaporization of iron 349.6 kj/mol
Answer:
150000 degrees
Explanation:
How to use system and habitable in a sentence
Answer:
The farthest habitable spot to the south The whole distribution system broke down.
Explanation:
A container of gas has a volume of 280 mL at a temperature of 22 Celsius if the pressure remains constant what is the volume 44 Celsius?
Answer:
300.9mL
Explanation:
Given parameters:
V₁ = 280mL
T₁ = 22°C
T₂ = 44°C
Unknown:
V₂ = ?
Solution:
To solve this problem, we apply Charles's law;
it is mathematically expressed as;
[tex]\frac{V_{1} }{T_{1} } = \frac{V_{2} }{T_{2} }[/tex]
We need to convert the temperature to kelvin;
T₁ = 22°C = 22 + 273 = 295K
T₂ = 44°C = 44 + 273 = 317K
Input the parameters and solve;
[tex]\frac{280}{295}[/tex] = [tex]\frac{V_{2} }{317}[/tex]
V₂ x 295 = 280 x 317
V₂ = 300.9mL
How many energy levels does the element helium have?
I appreciate the help!
Please try your best to answer this!
Answer:
Element Helium have 2 energy levels.
Explanation:
HELIUM - With the symbol He and the atomic number 2, helium is a chemical element. It is a colorless , odorless, tasteless, non-toxic, inert, monatomic gas that is the first in the periodic table in the noble gas group. Of all the elements, its boiling point is the lowest.
At about 24 % of the total elemental mass, which is more than 12 times the mass of all the heavier elements combined, it is present. In both the Sun and Jupiter, its abundance is identical to this. This is due to helium-4's very high nuclear binding energy (per nucleon) with respect to the next three elements following helium.
Hence , the answer is 2 energy levels in Helium atom.
HELPPP PLEASEEE!!! calculate the energy of radiation with a wavelength of 432 nm
Someone drops a book on the floor, and it makes a loud noise. At that time, you turn to look at the person who dropped the book. Turning and looking at the person who dropped the book is an example of a…
A. Phototropism
B. Response
C. Hydrotropism
D. Stimulus
Answer:
D
Explanation:
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
can someone help me please
Answer:
Particle energy
Explanation:
What is the mass of 5 mL. of a solution if the density of the solution is 1.5 g/mL.? Show work.
Answer:
The answer is 7.5 gExplanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volumeFrom the question
volume = 5 mL
density = 1.5 g/mL
We have
mass = 1.5 × 5
We have the final answer as
7.5 gHope this helps you
1. A sodium ion has 11 protons and 10 electrons. What is its charge?
+1
If sodium loses an electron, it now has 11 protons, 11 neutrons, and only 10 electrons, leaving it with an overall charge of +1. It is now referred to as a sodium ion.
