Answer:
HC2H3O2(I) + O2(g) ---> H2O(I) + CO2(g) ΔH= -72.35 kJ
Explanation:
We know that 5.0 g of acetic acid will contain, 5.0g/60 g/mol = 0.083 moles of acetic acid
Now from the reaction equation;
1 mole of acetic acid evolved -871.7 KJ of heat
0.083 moles of acetic acid will evolve 0.083 * -871.7 = -72.35 KJ
For 5.0 g of acetic acid, we can write;
HC2H3O2(I) + O2(g) ---> H2O(I) + CO2(g) ΔH= -72.35 kJ
An atom is found in group 17 and contains 10 neutrons. How many valence
electrons does it have? *
PLEASE HURRY !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! WILL GIVE BRAINLIEST
What type of rock is limestone? Describe how a limestone rock is likely to change over a long period of time.
Answer:
Over time, the limestone is broken down into its chemical parts and may come back to the surface as volcanic CO2 (in the atmosphere). From the atmosphere, the CO2 might again become part of the biosphere by molluscs or corals absorbing the CO2 to help make their shells
Explanation:
Over a long period of time, we would take a look at the rock "limestone" through the rock cycle. Limestone being a sedimentary rock would be converted to marble, a metamorphic rock if subjected to metamorphic conditions over an extensive period of time.
can someone help answer this? thanks!
if surface tension relies on intermolecular forces, how could you make surface tension decrease?
(think about how and where molecules bind to each other)
Answer:
We could make the surface tension to decrease by removing and causing a disruption to the intermolecular forces(hydrogen bonds).
Explanation:
To explain this answer, we will consider an experiment whereby a paper clip is made to rest at the top surface of water inside a container/beaker.
First of all, the intermolecular forces present in water are also known as hydrogen bonds.
It's relationship with surface tension is that when there is high surface tension in the water, this high tension will allow the paper clip to rest on top of the hydrogen bonds present at the top surface in between the water molecules.
However, the surface tension will decrease when we remove or cause a disruption to the intermolecular forces (hydrogen bonds).
Given that nitrogen forms
three bonds with hydrogen to
make NH3, how many hydrogen
atoms do you think will bond
with an atom of phosphorous?
Answer:
Three
Explanation:
Nitrogen and phosphorus are on the same group in the periodic table. Elements in the same group have similar chemical properties. This is because of the number of valence electrons that they share among each other.
The valence electrons are the outermost shell electrons found within an atom.
Nitrogen and phosphorus can both be found on the fifth group on the periodic table.
Their oxidation state is:
either 5 or 8-5 = 3Since phosphorus bonds with 3 hydrogen atoms, nitrogen will also do the same.
How many moles are present in 44.8 L of nitrogen gas (Na)?
Answer:
two moles
There are two moles.
Explanation:
Which of the following is not a form of precipitation?
A
groundwater
B
balls of hail
C
sleet
D
snowflakes
A.
Reason: cuz i need points noob
Given the following reaction, how many moles of iron(III)
oxide can be produced from 65.2 moles of iron?
4Fe + 302 → 2Fe2O3
Which of the following atoms would have a charge of +1?
An atom with 9 protons, 9 electrons, and 9 neutrons
An atom with 7 protons, 11 electrons, and 8 neutrons
An atom with 5 protons, 5 electrons, and 4 neutrons.
An atom with 6 protons, 5 electrons, and 7 neutrons
Answer: An atom with 6 protons, 5 electrons, and 7 neutrons
Explanation: In this case, neutrons do not matter as they have a charge of 0, or no charge. A proton has a charge of +1 and an electron has a charge of -1. Since there are 6 protons, the total charge of the protons would be +6. Since there are 5 electrons the total charge of the electrons would be -5. +6 - 5 would result in a charge of +1. This means that this atom would have an overall charge of + 1. Basically, if there is one more proton than electron, then the overall charge of the atom will be +1 but if there is one more electron than proton, then the overall charge of the atom will be -1.
Mixtures can be separated by physical processes.
A sequence of physical processes can be used to separate common salt (sodium chloride)
from a mixture containing sand and common salt only.
Give the order and the correct scientific term for the physical processes used to separate the
common salt from the mixture.
don't know sorry.........
Guys pleasee helpp 20 points
3rd law of thermodynamics..
2 Different Examples((Thnks))
Answer:
See explanation
Explanation:
The third law of thermodynamics states that "the entropy of a perfect crystal of a pure substance approaches zero as the temperature approaches zero" (Wikipedia).
One example of the third law of thermodynamics has to do with steam. Steam is gaseous water. Since it is a gas, its molecules are free to move around therefore its entropy is high. When the temperature of the steam is decreased below 100 degrees, the molecules of steam loose energy and turn into liquid water and do not move as freely as they did in the gaseous state. If the temperature is further decreased to yield ice at zero degrees, the molecules of water are "frozen" in their positions and the entropy of the system decreases to zero.
Also, the ions in ionic crystal solids move around when the substance is in solution or in molten state hence the substance conducts electricity. When the ionic substance is in solid state, the ions do not move about and the entropy of the solid system tends towards zero.
Humans have developed ways to increase the of their
environment. true or false
Answer:
True......................had to do this because we need atleast 20 letters
Water has a molar mass of 18.0 g/mol. How many particles of water do you drink if you drink 64 oz., or 1893 grams, of water in a day?
Answer:
[tex] \frac{1839}{18} = 102.16[/tex]
Take 102.16 and multiply by avogadros #
and you get 6.33 × 10^25 otherwise A
Answer:
Answer is A
Explanation:
I just took this.
What are two sources of phosphorous?
A. Cows
B. Erosion
C. stratosphere
D. Fossil fuels
E. Fertilizer
Answer: A. Cows
E. Fertilizer
Explanation:
What is the percent composition of sodium in Na3PO4? Express your answer to one decimal place. No units required.
Answer:
42.07%
Explanation:
Molar mass of Na3PO4 = 23×3 + 31 +16×4
= 69+ 31+64= 164 g/mol
Mass of Na in this compound is 69
Percentage of sodium in sodium phosphate = 69/ 164×100
Percentage of Na = 42.07%
Which organ system supports the body and allows it to move?
That would be the skeletal system, hope this helps ^^
Aluminum is used to build aero planes. Which two of its physical properties make it suitable for this use
Answer:
Titanium is another metal that's commonly used in aerospace engineering. It's strong, lightweight, Aluminum isn't the strongest metal, but it maintains a perfect balance of strength and low weight that make airplanes fly
Explanation:
vote mee as the brainliest
Answer:
it weight were so thin
explanation
With a weight roughly a third lighter than steel, it allows an aircraft to either carry more weight, or become more fuel efficient. High Strength — Aluminum's strength allows it to replace heavier metals without the loss of strength associated with other metals, while benefitting from its lighter weight
Uhm how to do this? I need answers to this please
Answer:
Hi - First you need to determine whether there is a metal or no and from there there are certain rules in order to name the compound. Here is a flowchart to try and help.
what does group 16 (oxygen family) have in common
Answer: here is your answer
Explanation:
The oxygen family consists of the elements that make up group 16 on the periodic table: oxygen, sulfur, selenium, tellurium, and polonium. These elements all have six electrons in their outermost energy level, accounting for some common chemical properties among them.
Answer:
they all have 6 valence electrons
Explanation:
all elements in group 16 have 6 valence electrons
What do the letters ESM stand for?
Answer:
European stability mechanism
What is the overall trend for ionization energy on the periodic chart?
Answer:
The general trend is for ionization energy to increase moving from left to right across an element period. Moving left to right across a period, atomic radius decreases, so electrons are more attracted to the (closer) nucleus.
Explanation:
Brainliest plz
Answer:
Ionization energy increases across the period and decreases down the group.
What is the molality of a solution made by dissolving 2 moles of NaOH in 6 kg
of water?
A. 0.33 mol/kg
B. 12 mol/kg
C. 3 mol/kg
D. 2 mol/kg
The molality of a solution : m = 0.33 mol/kg
Further explanationGiven
2 moles of NaOH in 6 kg of water
Required
The molality
Solution
Molality shows how many moles are dissolved in every 1000 grams of solvent.
m = n x (1000/p)
m = Molality
n = number of moles of solute
p = solvent mass (grams)
Input the value :
solute : NaOH
solvent : water
m = 2 moles : 6 kg
m = 0.33 mol/kg
You need to make an aqueous solution of 0.150 M sodium fluoride for an experiment in lab, using a 500 mL volumetric flask. How much solid sodium fluoride should you add?
Answer:
Explanation:
Solution required is .15 M 500 mL sodium fluoride .
molecular weight of sodium fluoride = 42
one mole of sodium fluoride = 42 grams
No of moles contained in the solution of .15M , 500 mL solution
= .15 x 0.5 moles = .075 moles
1 mole = 42 g
.075 moles = .075 x 42 = 3.15 grams .
So mass of sodium fluoride required = 3.15 g .
How many moles of H 2 will I need to make 5 moles of NH3?
12 SSO
Answer:
7.5 moles of hydrogen is required
Explanation:
Given data:
Number of moles of H₂ needed = ?
Number of moles of NH₃ = 5 mol
Solution:
Chemical equation:
N₂ + 3H₂ → 2NH₃
Now we will compare the moles of ammonia and hydrogen.
NH₃ : H₂
2 : 3
5 : 3/2×5 = 7.5 mol
Thus, 7.5 moles of hydrogen is required.
3
Which two elements are the most abundant in the Earth's crust?
OA. iron and magnesium
B. iron and nickel
Oc. silicon and magnesium
OD. silicon and oxygen
Novomatlan
Yes
Answer:
Look at the properties of Oxygen and Silicon - the two most abundant elements in the Earth's crust - by clicking on their symbols on the Periodic Table.
Explanation:
Answer:
D. silicon and oxygen
Explanation:
The most abundant elements on the earth's crust are silicon and oxygen. Silicon and oxygen forms a wide range of silicate minerals they are found in the crust.
There are many silicates which are derived from the basal units of silicon and oxygen combining together. Other atoms or elements then combines with the silicate framework.
Oxygen is about 46% abundant in the crust whereas silicon takes about 28% to be the second most abundant element on the crust.
Silicate minerals abounds in rocks and within the soil.
What part of the atom contains the protons and neutrons?
6. A father rabbit had long ears while the mother rabbit had short ears. Which of these statements
explains why one of the baby bunnies could have long ears?
a
The baby bunny inherited its copies of the gene for ear length from its father and not from
its mother. Those genes connect together to make its ears long.
b
The baby bunny inherited its copies of the gene for ear length from its father and not from
its mother. Just like its father's genes, those genes instruct for proteins that connect in
ways that make its ears long.
С
The baby bunny inherited one copy of the gene for ear length from its father and one copy
from its mother. That gene combination instructs for proteins that connect in ways that
make long ears.
d
The baby bunny inherited one copy of the gene for ear length from its father and one copy
from its mother. Those genes connect together to make its long ears.
Answer:
D if I’m correct
Explanation:
Although chemical digestion occurs throughout the digestive system, it mostly occurs in the A esophagus and stomach
B
liver and gall bladder
C
liver and pancreas
D
stomach and intestines
Physical and chemical properties are used to describe and identify matter. Physical properties can be observed without changing the identity of the substance. Chemical properties can be observed by attempting to change the identity of a substance. What are two physical and chemical properties that you can use to help you identify a substance?
Extensive properties, such as mass and volume, depend on the amount of matter that is being measured. ... Both extensive and intensive properties are physical properties, which means they can be measured without changing the substance's chemical identity
"Henry mixed salt and water together in a cup until he observed a clear solution. He measured the mass of the solution. Then he placed the cup outside for several sunny days during the summer. After a week, he observed that only solid salt remained in the cup and the mass had decreased. Henry concluded that a physical and chemical change occurred in this investigation."
Which statements correctly defend or dispute his conclusion?
A.)He is correct. Dissolving salt in water is a physical change, but evaporating the water is a chemical change. Formation of a solid is evidence that a chemical change occurred.
B.)He is correct. Evaporation is a physical change, but dissolving salt in water is a chemical change. The change in mass is evidence that a chemical change occurred.
C.)He is incorrect. Dissolving salt in water and evaporation of the water are both physical changes. The reappearance of salt is evidence that the change was reversible by a physical change, so it could not be a chemical change.
D.)He is incorrect. Dissolving salt in water and evaporation of the water are both chemical changes. The reappearance of salt is evidence that the change was reversible by a chemical change, so it could not be a physical change.
Answer:
C.)He is incorrect. Dissolving salt in water and evaporation of the water are both physical changes. The reappearance of salt is evidence that the change was reversible by a physical change, so it could not be a chemical change.
Explanation:
From the analogy of the problem presented, we can see that Henry is grossly incorrect. His conclusion from the process of the experiment he carried out is completely wrong.
Physical changes are changes that alters the physical properties of matter particularly the form and state.
Chemical changes leads to the formation of a new kind of matter.
We can see that since the salt was obtained back after evaporation, no change has occurred to it.
Therefore, evaporation in itself is a physical change process.
Answer:
c on ed
Explanation: