Answer: false
Explanation:
HELP ASAP - How much energy is lost when 80.0 grams of steam at 100.C turns into liquid water at 100.C?
Answer:
Q = 43,000 calories = 180,000 joules = 180 Kilojoules
Explanation:
Heat flow for phase change can be defined as Q = m·ΔHv
ΔHv = Heat of Vaporization for water = 540 calories/gram = 2259 joules/gram = 2.259 Kilojoules/gram
m = mass of object of interest ( in this problem 80 grams steam 100°C converting to 80 grams of water at 100°C
Q = m·ΔHv = 80g x 540 cals/g =43.200 calories x 4.184 joules/cal = 180,748.8 joules (calculator answer) => 180,000 joules (2 sig. figs.) = 180 Kj
how many Nitrogen are in 2AlN
Which of the following is the symbol for an element?
Co2
Ch4
C
H2o
6 How many moles are in a 321 g sample of magnesium?
F 13.2 mol Mg
G 13.4 mol Mg
H 13.6 mol Mg
J 13.8 mol Mg
Answer:
13.4mol of Mg
Explanation:
Given parameters:
Mass of magnesium = 321g
Unknown:
Number of moles = ?
Solution:
The number of moles of a substance is given as;
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
Molar mass of Mg = 24g/mol
Insert the parameters and solve;
Number of moles = [tex]\frac{321}{24}[/tex] = 13.4mol of Mg
A solution of silver chloride reacts with aqueous sodium sulfate to produce a precipitate and a solution.
When balanced, the coefficients for this chemical reaction, is?
Answer:
<br> a) Barium chloride and sodium sulphate aqueous solutions react to give insoluble barium sulphate and aqueous solution of sodium chloride.
How many phosphorus atoms are in two moles of the compound Mg3(PO4)2? O 4 atoms O 1.2 x 1023 O 2 atoms O 2.4 x 1023
The number of phosphorus atoms : 2.408 x 10²⁴
Further explanationThe mole is the number of particles(molecules, atoms, ions) contained in a substance
1 mol = 6.02.10²³ particles
Can be formulated
N=n x No
N = number of particles
n = mol
No = Avogadro's = 6.02.10²³
moles of Mg₃(PO₄)₂ = 2
moles of phosphorous(P) atoms in Mg₃(PO₄)₂ ⇒ mol ratio of elements in the compound(for P=2)
[tex]\tt 2\times 2=4[/tex]
The number of atoms of phosphorous(P) :
[tex]\tt 4\times 6.02\times 10^{23}=2.408\times 10^{24}[/tex]
the first plants to grow after a fire are called?
Answer:
Ephemerals
Explanation:
The first plants to move into the new bare ground after a wildfire are wildflowers or “weeds.” These fast-germinating, leafy herbaceous plants are also known as “forbs” or “ephemerals.” They quickly germinate, grow and produce a new crop of seeds.
Answer:
ephemeral
Explanation:
Which of the following is considered a compound?
1) N2
2) Na
3) BF3
PLEASE HELP.
how many grams of K2SO4 are in 1.18x10^24 atoms?
Answer:
Mass = 331.17 g
Explanation:
Given data:
Mass in gram = ?
Number of atoms of K₂SO₄ = 1.18 × 10²⁴ atoms
Solution:
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
1.18 × 10²⁴ atoms × 1 mol / 6.022 × 10²³ atoms
0.19× 10¹ mol
1.9 mol
Mass of K₂SO₄:
Mass = number of moles × molar mass
Mass = 1.9 mol × 174.3 g/mol
Mass = 331.17 g
The density of liquid Z is 0.9327 g/mL. A student masses a cup with a sample of liquid Z in it and finds the mass to be 50.7 g. The mass of the cup alone is 15.92 g. What is the volume of liquid Z in the cup? (Volume = mass/density)
Answer:
Try doing this: 50.7/.9327 for the answer.
Calculate the molar mass of a gas with a mass of 3.15 g, a pressure of 785 mmHg, and a temperature of 20 Celsius. The gas has a volume of 750 ml.
Answer:
Molar mass = 105 g/mol
Explanation:
Given data:
Mass of gas = 3.15 g
Pressure = 785 mmHg
Temperature = 20°C
Volume of gas = 750 mL
Molar mass of gas = ?
Solution:
Pressure = 785 mmHg (785/760 = 1 atm)
Temperature = 20°C (20+273 = 293 K)
Volume of gas = 750 mL (750 mL× 1 L/1000 mL = 0.75 L)
PV = nRT
R = general gas constant (0.0821 atm.L/mol.K)
1 atm× 0.75 L = n×0.0821 atm.L/mol.K × 293 K)
0.75 atm.L = n× 24.06 atm.L/mol
n = 0.75 atm.L / 24.06 atm.L/mol
n = 0.03 mol
Molar mass of gas:
Molar mass = Mass / number of moles
Molar mass = 3.15 g/ 0.03 mol
Molar mass = 105 g/mol
A student wants to find out if drinking coffee will affect the amount of sleep she has everyday. she collected data of cups of coffee that she drank to how many hours of sleep she got everyday. what would you plot on the x-axis?
We plot the cups of coffee drink on the X-axis, whereas hours of sleep are plotted on the Y-axis.
plotting graphs relationship between various sets of variables with respect to one another. the main use of a graph is it helps us to present data which are complex to describe in the text.Since in the problem it is given that, the student wants to record the hours of sleep which are affected by the number of cups of coffee consumed by her or him, therefore we will plot the number of cups of coffee on the X-axis and the number of hours of sleep will be plotted in Y-axis .
To learn more about Plotting graphs refer to the link https://brainly.com/question/3638574?referrer=searchResults.
#SPJ4
select a paragraph that best explain several ways to identify a chemical change through observiation alone?
A. a chemical change occurs when the composition of a substance is changed. chemical change requires the breaking of forming of chemical bonds during a chemical change. The result in arranging of atoms in substances to form the product of the chemical reaction which becomes brand new molecules. These new molecules cannot be easily research it back to their original state
B. sometimes it is difficult to tell if a chemical reaction has taken place. To help determine whether there has been a reaction, chemists consider a few basic indicators. These include a change in temperature, a change in color or the development of an odor.the formation of a participate or the formation of a gas may also indicate a chemical reaction
C. in a chemical alteration a temperature change occurs as a result of a breaking or formation of a chemical bond. When the chemical bonds of the reactants are broken sometimes excesses energy is released. These can cause he choose to be discharged leading to an increase in temperature . burning wood is an example of a reaction that releases at Energy as heat. A chemical cold pack in a first-aid kit in is an example of chemical reaction that absorbs heat energy rather than releasing it.this result in Cooling.
D. a chemical reaction may also release a gas for example a mix of a vinegar and baking soda will immediately start bubbling and foaming.the bubbles are a release of carbon dioxide gas a product of a chemical reaction between these two households substances
Answer:
ITS A OR B
Explanation:
What general trend do you observe in the periodic table of the Atomic Radius?
Answer:
Atomic radius Increases in groups from top to bottom and decrease in period from left to right.
Explanation:
40 points.
9. Key Concept How do measurements relate to
experimental science?
10. Key Concept How are accuracy and precision
evaluated?
11. Key Concept Why must a given measurement
always be reported to the correct number of significant figures?
12. Key Concept How does the precision of a calculated answer compare to the precision of the
measurements used to obtain it?
13. A technician experimentally determined the
boiling point of octane to be 124.1°C. The actual
boiling point of octane is 125.7°C. Calculate the
error and the percent error.
14. Determine the number of significant figures in
each of the following.
a. 11 soccer players
b. 0.070 020 meter
c. 10,800 meters
d. 5.00 cubic meters
15. Solve the following and express each answer in
scientific notation and to the correct number of
significant figures.
a. (5.3 104) (1.3 104)
b. (7.2 104) (1.8 103)
c. 104 103 106
d. (9.12 101) (4.7 102)
e. (5.4 104) (3.5 109)
9. Making correct measurements is fundamental to the experimental sciences.
10. Accuracy is the measured value compared
to the correct values. Precision is comparing more than one measurement.
11. The significant figures in a calculated
answer often depend on the number of
significant figures of the measurements
used in the calculation.
12. A calculated answer cannot be more precise than the least precise measurement
used in the calculation.
13. error = –1.6°C; percent error = 1.3%
14. a. unlimited
b. 5
c. 3
d. 3
15. a. 6.6 × 104
b. 4.0 × 10–7 c. 107
d. 8.65 × 10–1
e. 1.9 × 1014
Answer: number 9 is: Measurements are fundamental to experimental science. Number 10 is: To evaluate the accuracy of a measurement, the measured value must be compared to the correct value. To evaluate the precision of a measurement, you must compare the values of two or more repeated measurements. Number 11 is: Measurements must always be reported to the correct number of significant figures because calculated answers often depend on the number of significant figures in the values used in the calculation. Number 12 is: Usually a calculated answer cannot be more precise than the least precise measurement from which it was calculated. Number 13 is: 125.7−124.1=1.6 125.7 − 124.1 = 1.6 degrees Celsius. Number 14 is: a. 11 soccer players- 2 SF b. 0.070 020 meter- 5 SF c. 10,800 meters- 5 SF
d. 5.00 cubic meters- 1 SF.
Number 15 is: A)
Number of significant figures = 2
B)
Number of significant figures = 2
C).
Number of significant figures = 1
D).
Number of significant figures = 3
E).
Number of significant figures = 3
Explanation:
Can you help give examples of elements, compounds, and mixtures? My friend is having trouble with it.
Answer:
Elements are all the subtances on the periodic table. Compound are elements that are fused by chemical means like potassium chloride. Mixture are elements that are not chemically fused but just in a sense mixed together.
All atoms try to achieve---------------(minimum energy,stable energy,maximum energy,covalent energy)
Answer:
minimum energy
Explanation:
minimum energy means maximum stability
please mark me brainliest
How does one balance an equation?
Answer:
To make both sides of an equation equal, multiply the number of atoms in each element until both sides are equal.
Explanation:
The chemical equation is an equation in which the number of atoms of each element on the product side is equal to the number of atoms of each element on the reactant side. To make both sides of an equation equal, multiply the number of atoms in each of the elements on both the sides until both the sides become equal.
Which of the following is an example of a covalent compound?
Answer:
CCI2
Explanation:
What relationship do you observe between the temperature and density?
Answer:Density is directly proportional to pressure and indirectly proportional to temperature. As pressure increases, with temperature constant, density increases. Conversely when temperature increases, with pressure constant, density decreases.
Explanation:
hope this helped
What occurs to the kinetic energy when the mass moving object is doubled?
Answer:
Kinetic energy increases.
Explanation:
Kinetic energy is energy you get from moving. The equation for KE depends on mass as well as velocity. If you increase one of these factors, KE will increase too.
PLS HELP!!! Which of the following is NOT a basic assumption of the Kinetic Molecular Theory?
a. The size of the particles is negligibly small
b. The kinetic energy is proportional to the temperature
C. Collisions of particles is elastic
d. The quantity of particles is negligible
Answer:
it might be the second answer
What is the mass number of a sulfur (S) atom that has 17 neutrons?
what is the chemical equation for this?
Answer:
J
Explanation:
Chlorine Gas is Cl2 so if it isnt on the left as that its wrong.
Then on the products see that Fe III means Fe is +3 charge so we have to have 3 Cl to balance it to 0 since each cl as -1 charge.
FInally check if the equation is balanced J is maybe H but its to blurry to tell
You shoot a beam of 4.5 eV light at a metal surface and notice that electrons are being
released from the metal. What will happen if you then increase the intensity of the 4.5
eV light?
O The metal will bend and warp.
O Nothing, the energy of the light is the same.
O More electrons would be released.
Photons would come off at higher speeds.
If you then increase the intensity of the 4.5 eV light, you will notice that the photons would come off at higher speeds.
What is intensity of light?
Light intensity refers to the strength or amount of light produced by a specific lamp source.
Intensity of light measures of the wavelength-weighted power emitted by a light source.
Mathematically, the intensity of light source is given as;
I = P/A
where;
P is the power of the incident light (photon energy per second )A is the unit areaIncreasing the light intensity (photon energy per second per unit area) increases the rate at which electrons leave the metal, and the electrons have more kinetic energy.
Thus, if you then increase the intensity of the 4.5 eV light, you will notice that the photons would come off at higher speeds.
Learn more about intensity of light here: https://brainly.com/question/28145811
#SPJ1
A student prepared this table to gather information about digestion. Digestion of Food Column A Column B Physical Changes Chemical Changes The results of which investigation would be entered in Column A of the table? A. How do mitochondria release the energy in food molecules? B. Which type of teeth are most important in crushing food? C. What chemicals in the stomach are most important in breaking down proteins? D How do substances released by the pancreas affect the rate of digestion?
Answer:
B. Which type of teeth are most important in crushing food?
Explanation:
According to the question physical changes ought to be entered into column A while chemical changes ought to be entered into column B.
The crushing of food is a physical change. It does not involve any chemical transformation of the food material.The other options involve some sort of chemical transformation taking place on the food material being digested.
a collective term for several mechanical weathering processes induced by stresses created by the freezing of water into ice. is what? (its ice something) idk the other word:(
Answer: Frost weathering is a collective term for several mechanical weathering processes induced by stresses created by the freezing of water into ice.
is it true that Einstein's equation E=mc2 states that matter can be converted to energy. This is an exception to the Law of Conservation of Mass.
The famous formula E=mc^2 really says that mass and energy are the same thing, but measured in different units. So the separate laws of conservation- one for mass and the other for energy- are now merged into one law.
Einstein's theory of special relativity (1905) shows that matter (as mass) and energy can be converted into each other according to the famous equation E = mc2, where E is energy, m is mass, and c is the speed of light.
Hope It helps you.
In testing for the presence of lead 2+ ions in solution, a student addes a
solution of sodium nitrate. What will be the conclusion of the test if no
precipitate forms? *
An object's velocity can be described by its acceleration and direction.
True
False
Answer:
False
Explanation:
An object's velocity can be described by it's direction. Because velocity is a vector. Besides velocity and acceleration are different units they can't be described by each other.