Answer:
please give me brainlist and follow
Explanation:
Contamination of ground water can result in poor drinking water quality, loss of water supply, degraded surface water systems, high cleanup costs, high costs for alternative water supplies, and/or potential health problems. The consequences of contaminated ground water or degraded surface water are often serious.
what is a chemical equation
Answer:
"Symbolic representation of a chemical reaction in the form of symbols and formulae"
Answer:
A chemical equation is the symbolic representation of a chemical reaction in the form of symbols and formulas.
Explanation:
Example- Zinc metal reacts with dilute sulphuric acid to form zinc sulphate and hydrogen gas. This equation is written as: Zn+H2SO4→ZnSO4+H2.
What is the mass of sulfuric acid, H2SO4, that is contained in 2.0 L of a 5.85 M solution ?
A-1147.44 grams
B- 0.12 grams
C-11.7 grams
D-98.07 grams
Which substance cannot be separated or broken down into simpler substances by chemical means?
table salt
gold wire
candle wax
water vapor
Answer: Gold Wire
Explanation:
Out of all of these options only gold wire is an element, elements are pure and cannot be broken down by any chemical means
hope it helped, good luck :)
18) What is the following number representing: 10m/s West *
3 points
Force
Acceleration
Mass
Area
Pressure
Velocity
Speed
Impulse
Momentum
Speed
Explanation:
The distance travelled by a body per unit time
What would it mean if a forecaster claimed, “There will be east winds of 25 to 30 mph."
Answer: It would mean that there is wind originating from the east and blowing west at 25 - 30 mph
Plutonium is a radioactive material, exposure to which is hazardous to human health, and is one of the few materials that can be used to make a nuclear weapon. The time it takes for half of any initial quantity of plutonium to decay into stable non-radioactive products is roughly:
Answer:
24,000 years
Explanation:
Gerald's science teacher mixed liquid X and liquid Y, both at room-temperature, in a large beaker. two beakers of clear solutions to the left of a right-pointed arrow, and a large beaker with a clear solution to the right of the arrow The mixture in the large beaker still looked clear like water, but when the students, one at a time, carefully touched the outside of the large beaker, it felt warm to the touch. Why did the large beaker most likely feel warm? A. The two liquids were not soluble in water. B. The release of a gas heated the solution. C. A chemical reaction produced a new substance. D. The energy of mixing warmed the liquids.
Answer:
c
Explanation:
A chemical reaction produced a new substance. In a chemical reaction, the atoms that make up the reactants are rearranged to produce various products.
What is chemical reaction?chemical reaction, the transformation of one or more chemicals (the reactants) into one or more distinct compounds (the products). Chemical elements or chemical compounds make up substances.
A chemical reaction is one in which two or more reactants will react to form a new substance. When new substance will form it will produce heat. Therefore, when science teacher was mixing two liquids it was generating heat.
Heating a substance allow molecules to move faster. When heat is given to the object it will move fast. When heat will apply to a solid it will turn into liquid. When heat is supplied to the liquid it will turn into gas.
Therefore, A chemical reaction produced a new substance. In a chemical reaction, the atoms that make up the reactants are rearranged to produce various products.
To learn more about chemical reaction, refer to the link:
https://brainly.com/question/22817140
#SPJ5
how did the idea of what a cell was develop overtime
Answer:
experiments
Explanation:
I am not sure but heres my take
Answer:
It was only after the invention of electron microscope that the idea developed
How are a moon and an asteroid different? (2 points)
a
A moon revolves around an asteroid, while an asteroid rotates around its axis.
b
A moon revolves around a planet, while an asteroid revolves around a star.
c
A moon revolves around a star, while an asteroid rotates around its axis.
d
A moon rotates around its axis, while an asteroid revolves around a planet.
Answer:
B
Explanation:
Asteroid - A rock that rvolves arounf the sun / star.
Moon - A natural satillite that revolves around earth/ planet.
PLZ HELP!
Are water waves transverse or longitudinal? How do you know? IN YOUR OWN WORDS.
Explanation:
Transverse waves are always characterized by particle motion being perpendicular to wave motion. A longitudinal wave is a wave in which particles of the medium move in a direction parallel to the direction that the wave moves.
N3- ion name pls help!!
Answer:
N with a charge of (-3) is nitride
Explanation:
You are given a 1.55 g mixture of calcium nitrate and calcium chloride. You dissolve this mixture in 20 mL of water and add an excess of 0.300 M silver nitrate. You collect and dry the resulting precipitate and determine it has a mass of 0.535 grams. Calculate the percent calcium chloride in the original mixture.
Answer:
13.4 (w/w)% of CaCl₂ in the mixture
Explanation:
All the Cl⁻ that comes from CaCl₂ (Calcium chloride) will be precipitate in presence of AgNO₃ as AgCl.
To solve this problem we must find the moles of AgCl = Moles of Cl⁻. As 2 moles of Cl⁻ are in 1 mole of CaCl₂ we can find the moles of CaCl₂ and its mass in order to find mass percent of calcium chloride in the original mixture.
Moles AgCl - Molar mass: 143.32g/mol -:
0.535g * (1mol / 143.32g) = 3.733x10⁻³ moles AgCl = Moles Cl⁻
Moles CaCl₂:
3.733x10⁻³ moles Cl⁻ * (1mol CaCl₂ / 2mol Cl⁻) = 1.866x10⁻³ moles CaCl₂
Mass CaCl₂ -Molar mass: 110.98g/mol-:
1.866x10⁻³ moles CaCl₂ * (110.98g/mol) = 0.207g of CaCl₂ in the mixture
That means mass percent of CaCl₂ is:
0.207g CaCl₂ / 1.55g * 100 =
13.4 (w/w)% of CaCl₂ in the mixtureI
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Which of the following hydrogen ion concentrations represents a solution with acidic
properties?
A
?
1 x 10-8 M
В.
?
1 x 10-2 M
C
1 x 10-11 M
D
1x 10-13 M
Activity Index
A
Answer:
A
Explanation: 11/22
Se mezclan 20 gramos de agua (1cal/g°C) a 40 °C con 15 gramos de alcohol (0,58cal/g°C) a 30 °C. ¿Cuál ha sido la temperatura de equilibrio térmico?
Answer:
[tex]T_{EQ}=37\°C[/tex]
Explanation:
¡Hola!
En este caso, para los problemas de equilibrio térmico, consideramos que la energía liberada por la sustancia que inicialmente está caliente (agua), es absorbida por la sustancia que inicialmente está fría (alcohol); thus, we can write:
[tex]Q_{agua}=-Q_{alcohol}[/tex]
La cual puede ser escrita en términos de masa, calor specifico y temperaturas:
[tex]m_{agua}C_{agua}(T_{EQ}-T_{agua})=-m_{alcohol}C_{alcohol}(T_{EQ}-T_{alcohol})[/tex]
De este modo, al resolver para la temperature de equilibrio térmico, obtenemos la siguiente expresión:
[tex]T_{EQ}=\frac{m_{agua}C_{agua}T_{agua}+m_{alcohol}C_{alcohol}T_{alcohol}}{m_{agua}C_{agua}+m_{alcohol}C_{alcohol}}[/tex]
Así, al reemplazar los valores en esta, obtenemos:
[tex]T_{EQ}=\frac{(20g)(1cal/g\°C)(40\°C)+(15g)(0.58cal/g\°C)(30\°C)}{(20g)*(1cal/g\°C)+(15g)(0.58cal/g\°C)} \\\\T_{EQ}=37\°C[/tex]
¡Saludos!
Most of the world’s energy comes from what three sources?
These energy sources are called ______________fuels and they are _____________________ resources.
Answers:
Most of the world’s energy comes from what three sources?
Oil, coal, and gas.
These energy sources are called fossil fuels and they are non-renewable resources.
Fuel type: oil
How it's formed: from the remains of ancient marine organisms
Its uses: transportation, industrial power, heating and lighting, lubricants, petrochemical industry, and use of by-products
Fule type: coal
How it's formed: when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial
Its uses: electricity generation, metal production, cement production, chemical production, gasification, and other industrial uses
Fuel type: gas
How it's formed: decomposed organic matter mixed with mud, silt, and sand on the seafloor
Its uses: heating & cooling buildings, cooking foods, fueling vehicles, and electricity generation
A solution of 12M HCl is diluted so that it goes from 550mL to a total volume of 1000mL. What is the new concentration of the solution?
Answer:
6.6M
Explanation:
C=concentration
V=Volume
C1V1=C2V2
rearrange formula to find C2
(C1V1)/V2= C2
(12M x 550mL)/1000mL= C2
6600M*mL*/1000*mL* =C2 (cancel units)
6.6M=C2
Which statement about elements is true?
All substances are made up of elements.
There are approximately 50 elements.
An element is made up of different types of atoms.
Most elements are nonmetal.

Answer:
first one is right.
there are 117 elements, so 2nd option is wrong.
elements are made up of one type of atoms, so 3rd is also wrong.
most elements are metal. so 3rd is wrong
why is zinc more electropositive than iron?
Answer:
Zinc has more power although iron has a stong bond with metal
Explanation:
Brainliest answer?
Answer:
Zinc has more negative electrode reduction potential than iron. Zinc is more easily oxidized than iron, zinc has a lower reduction potential.
Explanation:
Compute the percentage of error to the nearest tenth in the student’s calculation if the actual specific heat value for aluminum is 0.9J:g*C.
Complete Question:
1. A block of aluminum with a mass of 140 g is cooled from 98.4°C to 62.2°C with a release of 4817 J of heat. From these data, calculate the specific heat of aluminum.
a. Compute the percentage of error to the nearest tenth in the student's calculation if the actual specific heat value for aluminum is 0.9 J/g°C
Answer:
Percent error = 55.56 %
Explanation:
Given the following data;
Mass = 140 grams
Initial temperature = 62.2°C
Final temperature = 98.4°C
Quantity of heat = 4817 Joules.
To find the specific heat capacity;
Heat capacity is given by the formula;
[tex] Q = mcdt[/tex]
Where;
Q represents the heat capacity or quantity of heat. m represents the mass of an object. c represents the specific heat capacity of water. dt represents the change in temperature.dt = T2- T1
dt = 98.4 - 62.2
dt = 36.2°C
Making c the subject of formula, we have;
[tex] c = \frac {Q}{mdt} [/tex]
Substituting into the equation, we have;
[tex] c = \frac {4817}{140*36.2} [/tex]
[tex] c = \frac {4817}{5068} [/tex]
Specific heat capacity, = 0.95 J/g°C
b. To find the percentage error;
Given the following data;
Actual specific heat capacity = 0.9 J/g°C
Experimental specific heat capacity = 0.95 J/g°C
Percent error can be defined as a measure of the extent to which an experimental value differs from the theoretical value.
Mathematically, it is given by this expression;
[tex] Percent \; error = \frac {experimental \;value - actual \; value}{ actual \;value} *100[/tex]
Substituting into the formula, we have;
[tex] Percent \; error = \frac {0.95 - 0.9 }{ 0.9} *100[/tex]
[tex] Percent \; error = \frac {0.5}{0.9} *100[/tex]
[tex] Percent \; error = 0.5556 *100[/tex]
Percent error = 55.56 %
What is so important about DNA? Select all correct answers.
A. DNA is found in all organisms and carries instructions to build those organisms
B. DNA found in one organism probably shares similar instructions found in another species
C. DNA is composed of only four bases that repeat in a sequence that is different for each
species
D. Some organisms don't actually have DNA
E. The DNA of each organism is made out of different types of chemicals
Answer:
A and C
Explanation:
DNA is what makes up you and me and DNA is composed of four bases adenine, guanine, thymine, and cytosine. The others are not true.
Which types of chemical reactions are
considered opposites of one another?
Answer:
Hi
Explanation:
Decomposition reactions are really the opposite of combination reactions. In decomposition reactions, a single compound breaks down into two or more simpler substances (elements and/or compounds).
Explanation:
Decomposition chemical reactions
Decomposition reactions are really the opposite of combination reactions. In decomposition reactions, a single compound breaks down into two or more simpler substances (elements and/or compounds).
The decomposition of water into hydrogen and oxygen gases
and the decomposition of hydrogen peroxide t form oxygen gas and water
are examples of decomposition reactions.
What types of elements [metals/nonmetals] are found in each of the compounds?
Not a simple answer please
Explanation:
List of All Elements That Are Nonmetals
Hydrogen (sometimes)
Carbon.
Nitrogen.
Oxygen.
Phosphorus.
Sulfur.
Metals:-
Gold.
Silver.
Iron.
Copper.
Nickel.
Aluminum.
Mercury( Liquid metal)
Titanium.
Fluorine.
How is it possible for scientists to know the composition of stars without traveling to the star?
Answer:
One of the most common methods used today to determine the composition of stars is spectroscopy.
Explanation:
Spectroscopy is the study of the interaction between matter and electromagnetic radiation as a function of the wavelength or frequency of the radiation.
Define the law of conservation of charge and provide an example.
Define opposite charges attract and like charges repel and provide an example.
Define Electricity along with an example.
Answer:
Conservation of Charge is the principle that the total electric charge in an isolated system never changes. The net quantity of electric charge, the amount of positive charge minus the amount of negative charge in the universe, is always conserved.
The particles of a substance lose energy and change from
a disordered structure with large distances between the particles to
a loosely ordered state.
Which change of state is described?
Answer:
A Liquid
Explanation:
structure with large distance (gas) than goes to a loosely ordered state (liquid)
I hope this helps
What is the mass of 925.4 L of hydrogen gas at STP?
Answer:
If this is an idea gas then 1mol takes up 22.4L.
So, knowing how many L you have you can figure out how many mole syou have by doing a simple equation:
[tex]\frac{1mol}{y} =\frac{22.4L}{925.4L}[/tex]
Solve for y.
Then, since you know how many moles you have use the ptable https://ptable.com/#Properties to figure out the mass in grams.
NOTE: The ptable tells you that 1mol of H = 1g.....so this should be an easy calculation :) enjoy
5 The atoms of a certain element each contain 36 protons and 8 valence electrons. Which
statement correctly identifies this element and describes its chemical reactivity? (8.58)
A The element is krypton, Kr, and it is not very reactive.
B The element is chlorine, Cl, and it is highly reactive.
C The element is krypton, Kr, and it is highly reactive.
D The element is chlorine, Cl, and it is not very reactive.
Answer:
dfdfaxc b
Explanation:
Write the formula for Zn+2 (SO4)-2
Answer:
Zn2 + SO4 = Zn2(SO4)2
Explanation:
Which observation is true about the result of mixing kernel corn and oil?
A. The kernel dissolved in the oil.
B. The kernel corn floated above the oil
C. The kernel corn did not dissolve completely.
D. The kernel corn settled down at the bottom of the glass.
Answer:
A.The kernel dissolved in the oil.
9. What happens to the cell outside of the nucleus when the virus has been copied so many times? a. The cell fights back b. The cell gets help from its neighbor cells C. The cell gets help from white blood cells d. The cell is destroyed
Answer: it think the answer is c.) The cell gets help from white blood cells or b.) The cell gets help from its neighbor cells.
Explanation:
