explain why almunium is often used for long distance over head electric cables (high voltage)
Answer:
because it does not cost much and can be found easily. due to their low resistance and excellent conductivity.
Explanation:
20 points be right this is my final!!!
How many moles is 2.50 grams of oxygen?
Answer:
Mole is a number that connects mass of a substance with its number of particles. 2500 g of O2 = 1/32 x 2500 = 78.125 moles
Explanation:
have a great day
How does thermal energy flow?
Answer:
Thermal energy typically flows from a warmer material to a cooler material.
Explanation:
Read this sentence from Chapter One of Jack London’s The Call of the Wild.
Buck rushed at the splintering wood, sinking his teeth into it, surging and wrestling with it. Wherever the hatchet fell on the outside, he was there on the inside, snarling and growling, as furiously anxious to get out as the man in the red sweater was calmly intent on getting him out.
What is a good prediction question to ask after reading this excerpt?
Answer:
b)
Explanation:
It shows the natrual proggresion of a story and helps blend the narrtive together.
Answer:B
Explanation: i took the quiz on edge
Look at the graph. Which part of the line shows a time
when the object was not moving?
how to tell if something is a strong or weak acid or base
Answer:
It basically depends upon the pH value of that acid or Base. That's how you can determine whether the substance is a strong or weak acid/base. We have a pH scale ranging from 1 to 14, where 7 is the neutral point. Any substance having a pH of 7 means it is neither an acid nor a Base, but neutral in nature, such as water([tex]H_{2}O[/tex]). Now, if the pH is less than 7, the substance is an acid, similarly if the pH is more than 7, it is a base. As the pH DECREASES, the substance becomes more acidic, on the other hand as the pH INCREASES, the substance becomes more basic. This way you can compare between pH values of two substances and tell which one is stronger or weaker.
For Acids:
If a substance's pH is between 1 and 7 it is an acid. If it is more towards 1, it's a strong acid and if it's more towards 7 it is a weak acid.
For Bases:
If a substance's pH is between 7 and 14 it is a base. If it is more towards 14, it's a strong base and if it's more towards 7 it is a weak base.
Hope that helps...
people tint their car windows to stop what
Answer:
Reflection
Explanation:
Answer:
b
Explanation:
noble gases are used in many situations where a safe and constant environment must be maintained. for example, helium is used to provide a protective atmosphere for making fiber optics and semiconductors. argon is used to fill incandescent and flourescent light bulbs to prevent oxygen from corroding the hot filament. why are noble gases used in these situations?
Answer:
Noble gases have a complete valence electron shell making them stable and nonreactive.
Explanation:
Elements that become cations during bonding become smaller as a result.
A.
True
B.
False
which particle diagram shown above best represents the strongest intermolecular force between two ethanol, c2h6o, molecules?
The strongest intermolecular bonding in ethanol is hydrogen bonding.
Intermolecular forces are the forces that hold two molecules of a substance together in a given state of matter. For ethanol, the strongest intermolecular force is hydrogen bonding.
Hydrogen bonding occurs when hydrogen is directly linked to a highly electronegative element such as oxygen, nitrogen, fluorine or sulfur. The existence of intermolecular hydrogen bonds accounts for unusual properties such as abnormally high melting and boiling points.
Learn more about intermolecular forces: https://brainly.com/question/17111432
What is the mass number (A) of an atom that has an atomic number (Z=26) with 29 neutrons and 26 electrons?
Answer:
A = 55
Explanation:
The atomic number is the number of protons also = the number of electrons, so basically we have 29 neutrons, 26 electrons and 26 protons. Anyway, it's asking the mass number which is the neutrons + the protons, so you just take 29+26 = 55
Atomic number=26
Neutrons=29
Electrons=26
Mass number=Proton+neutron
Protons=26
Mass number=26+29
=55
If a sample of gas at constant temperature has its pressure doubled, what will happen to its volume?
Answer:
it'll halve
Explanation:
the gas is compressed with twice the pressure. The volume will be halved.
im certain
Different isotopes of an element have different numbers of:
Explanation:
Different isotopes of an element have different numbers of mass number
Write a balanced equation and name the products of the reaction CaCl2+Na3(PO4)
Answer:
3CaCl2 + 2Na3(PO4) → Ca3(PO4)2 + 6NaCl
Explanation:
DOUBLE REPLACEMENT REACTION
CaCl2 + Na3(PO4) → Ca3(PO4)2 + NaCl
3CaCl2 + 2Na3(PO4) → Ca3(PO4)2 + 6NaCl
calcium chloride + sodium phosphate → calcium phosphate + sodium chloride
Hope that helps
what is the speed of a skater who travels a distance of 210 m in a time of 10 seconds
Answer:
Speed =d/t. 200÷10=21÷1000=0.021 km/h
Explanation:
S=D/T
how many atoms of mercury are in 50.15 g of mercury?
Answer:
please mark brainliest
Explanation:
The correct answer to this question is 0.2500 mol
Formula to calculate moles:
Moles = mass ÷ molar mass (n=m/M)
Mass = 50.15g
Atomic mass: 200.59 amu
Moles = 50.15g/200.59
= 0.2500 mol.
Which of the following compounds will have the highest boiling point?
MgCl2
CO2
C12H22O12
,
H2O
for the reaction, Pb(no3)2 + 2kI yields pbi 2 + 2 kno3, how many moles of lead iodine are produced from 300 g of potassium iodine
A molecular compound is found to consist of30.4% nitrogen and 69.6% oxygen. Ifthe molecule contains 2 atoms of nitrogen, what is the molar mass of the molecule
Answer:
92.01 g/mol
Explanation:
So first you need to find the empirical formula by the percents. That would be, assuming that you have 100 grams of the the sample, divide each quantity of each element found by its respective molar mass.
30.4 g of N ÷ 14 g/mol N= 2.17 mol of N
69.6 g of O ÷ 16g/mol= 4.35 mol of O
You can establish now the empirical formula.
N2.17O4.35,
but since you can't have a decimal subscript, you divide each subscript by the minimum subscript
NO2
So then you're said that the molecular formula derived from that empirical formula has 2 nitrogen, so you multiply all the subscripts, by 2:
N2O4
-Dinitrogen Tetraoxide
-Nitrogen oxide (IV)
Then all you have to do is find the molecular mass of the compound using the periodic table and what you obtain is the molar mass.
remember: molecular mass is correspondent to molar mass.
This is my class group-work with my friends but we are stuck on this question.
Explanation:
It has to be C, because Carbon can bond with four other atoms and is like a four-hole wheel.
(Sorry if my elplanation was kinds choppy Oof, helpfully it makes sense?)
9
Ammonia is manufactured from nitrogen and hydrogen by the Haber process.
N2(g) + 3H2(g)2NH3(g)
What is the percentage yield when 60 kg of ammonia is produced from 60 kg of hydrogen?
A
5.9%
B
17.6%
с
35.3%
D
50.0%
Answer:
B
17.6%
Explanation:
1. Percentage yield = (Actual yield/theoretical yield) x 100
2. You know actual yield of ammonia (60kg) so you need to work out theoretical yield.
3. mols of hydrogen = m/mr = 60,000/2 = 30,000 mols.
4. 3:2 ratio so (30,000/3) x 2 = 20,000 mols of Ammonia.
5. Therefore mass of ammonia = mr x mols = 20,000 x 17 = 340,000 grams
6. So percentage yield is (60,000/340,000) x 100 = 17.6
PLEASE DON'T PUT ANSWER AGAINST GUIDELINES!!!
Answer:
160.3 g S
Explanation: there you go
What happens when a solid is exposed to sub-zero temperatures?
Answer:
A substance may undergo phase change from a solid to a gas or from a gas to a solid if the temperature it is exposed to is changed very quickly. If the temperature around a solid is raised very quickly, it can sublimate, or phase change from a solid to a gas without existing as a liquid.
Explanation:
Which of the following statements is true about atomic spectra? I. The line spectra of elements are evidence that electron energies are quantized II. Energy is emitted from atoms as they move from lower energy levels to higher energy levels III. Energy is emitted from atoms as they move from higher energy levels to lower energy levels IV. Neutral atoms in the ground state emit light spontaneously
The line spectra of an atom offers conclusive evidence that electron energies are quantized.
Neils Bohr showed that electrons in an atom can absorb or emit energy when they move from one energy level to another. This principle is the basis upon which the spectra of atoms is built.
The true statements about the atomic spectra is;
The line spectra of elements are evidence that electron energies are quantized Energy is emitted from atoms as they move from higher energy levels to lower energy levelsLearn more about atomic spectrum: https://brainly.com/question/2049494
how many grams are in 4.07x10^15 molecules of calcium hydroxide
There are 5.01 × 10-⁷grams in 4.07 x 10¹⁵molecules of calcium hydroxide.
HOW TO CALCULATE MASS:
The mass of a substance can be calculated by multiplying the number of moles in the substance by its molecular mass.
However, given that the number of molecules in calcium hydroxide is 4.07 x 10¹⁵molecules, we need to calculate the number of moles in Ca(OH)2 as follows:
no. of moles of Ca(OH)2 = 4.07 x 10¹⁵ ÷ 6.02 × 10²³
no. of moles = 0.676 × 10-⁸
no. of moles = 6.76 × 10-⁹ moles.
Molar mass of Ca(OH)2 = 74.093 g/mol
Mass of Ca(OH)2 = 74.093 × 6.76 × 10-⁹ moles
Mass = 5.01 × 10-⁷grams.
Therefore, there are 5.01 × 10-⁷grams in 4.07 x 10¹⁵molecules of calcium hydroxide.
Learn more about how to calculate mass at: https://brainly.com/question/8101390?referrer=searchResults
Which model of the atom is thought to be true?
A. Protons, electrons, and neutrons are evenly distributed throughout the volume of the atom.
B. The nucleus is made of protons, electrons, and neutrons.
C. Electrons are distributed around the nucleus and occupy almost all the volume of the atom.
D. The nucleus is made of electrons and protons.
Its A. Explanation:I just know
Alkaline batteries adopted their name from the _____ that is present in the reactions at both the zinc anode and the MnO2 cathode.
Answer:
hydroxide ion
Explanation:
The alkaline battery got this name because it has an alkaline electrolyte of potassium hydroxide.
Match each type of reaction to its amount of potential energy. (PLEASE HELP )
It accounts for the differences in the behavior of particles in different states. *
Answer:
Matter
Explanation:
Solids, liquids, and gases are the three types of matter that can be found in the world around us today. In solids, all of the particles are close together. They move more in liquids, but they are spread out in gas.