Answer:
The periodic table of elements puts all the known elements into groups with similar properties. This makes it an important tool for chemists, nanotechnologists, and other scientists. If you get to understand the periodic table and learn to use it, you'll be able to predict how chemicals will behave.
Answer:
Okayy
Explanation:
The periodic table arranges the chemical elements
All the members of a family of elements have the same number of valence electrons and similar chemical properties. The horizontal rows on the periodic table are called periods
It have many properties. Each column is called a group.
ALSO Metals are placed on the left-hand side of the periodic table , and non-metals on the right.
Metalloids can also be called semimetals. On the periodic table, the elements colored yellow, which generally border the stair-step line, are considered to be metalloids.
Water + Heat
What is proof of a Chemical Reaction?
Evapotranspiration is the process by which
O plants give off water vapor as a waste product as they process energy.
O evaporated water moves through the air and causes differences in climate.
O None of the above.
O rock is shaped as water evaporates off of its surface.
Answer:
A: plants give off water vapor as a waste product as they process energy
Explanation:
Evapotranspiration in plants is defined as the process whereby water is evaporated from its leaves through transpiration during the process of photosynthesis. Different factors like wind, humidity, temperature and availability of water could make it vary.
Comparing all the options, to this definition, the correct answer is Option A.
Find the wavelength of the electromagnetic radiation with a frequency of 3x10^-18Hz PLEASE ANSWER
Answer:
λ = 1×10²⁶m
Explanation:
Given data:
Wavelength of radiation = ?
Frequency of radiation = 3×10⁻¹⁸Hz
Solution:
Formula:
c = f × λ
c = speed of wave = 3×10⁸ m/s
by putting values,
3×10⁸ m/s = 3×10⁻¹⁸Hz × λ
λ = 3×10⁸ m/s / 3×10⁻¹⁸s⁻¹
λ = 1×10²⁶m
Suppose an AM talk radio station broadcasts radio waves with a frequency of 930. kHz. Calculate the wavelength of these radio waves.
Round your answer to 3 significant digits.
Answer:
323 m.
Explanation:
From the question given above, the following data were:
Frequency (f) = 930 KHz
Wavelength (λ) =?
Next, we shall convert 930 KHz to Hz. This can be obtained as follow:
1 KHz = 1000 Hz
Therefore,
930 KHz = 930 KHz × 1000 Hz / 1 KHz
930 KHz = 93×10⁴ Hz
Thus, 930 KHz is equivalent to 93×10⁴ Hz
Wavelength (λ) of a wave and the frequency (f) are related according to the equation:
Velocity = wavelength × frequency
v = λf
With the above formula, we can obtain the wavelength of radio wave as follow:
Frequency (f) = 93×10⁴ Hz
Velocity (v) of electromagnetic wave = 3×10⁸ m/s
Wavelength (λ) =?
v = λf
3×10⁸ = λ × 93×10⁴
Divide both side by 93×10⁴
λ = 3×10⁸ / 93×10⁴
λ = 323 m
Thus, the wavelength of the radio wave is 323 m
Definition: This is two or more elements chemically combined in a fixed ratio.
Answer:
Compound
Explanation:
Compounds – Compounds are chemical substances made up of two or more elements that are chemically bound together in a fixed ratio.
Example of compounds includes water (H2O), Hydrogen Peroxide (H2O2), etc. You could see water’s chemical formula, it says it has 2 atoms of Hydrogen combined with 1 atom of oxygen and in hydrogen peroxide, it has 2 atoms of hydrogen and two atoms of oxygen.
A technician measures the weight of a reagent . The weight is 3269 g. What is the weight in kilograms ? Write your answer as a decimal
Answer:
3.269 kg
Explanation:
1000g = 1 kg. Since kg is the larger unit, you need to divide by 1000 to get kilograms. You can do the problem as a unit conversion:
3269 g × 1 kg = 3.269 kg
1000g
Hope this is helpful!
How many molecules are there in a 42.3 g sample of water, H2O?
Answer:
In order to figure out how many molecules of water are present in that
48.90-g
sample, you first need to determine how many moles of water you have there.
As you know, a mole is simply a very large collection of molecules. In order to have one mole of something, you need to have exactly
6.022
⋅
10
23
molecules of that something - this is known as Avogadro's number.
In order to get to moles, you must use water's molar mass. A substance's molar mass tells you the mass of one mole of molecules of said substance.
Water has a molar mass of
18.015 g/mol
. This means that one mole of water molecules has a mass of
18.015 g
.
So, to sum this up,
6.022
⋅
10
23
molecules of water will amount to
1 mole
of water, which in turn will have a mass of
18.015 g
.
Explanation:
what is chemical reaction?
Answer:
a process that involves rearrangement of the molecular or ionic structure of a substance, as distinct from a change in physical form or a nuclear reaction
Which of the following is a chemical weathering agent?
1.) acid produced by plants growing on rocks
2.) growing tree roots
3.) burrowing animals
4.) ice wedging
PLEASE HELP ME FAST ASAP
Answer:
1. acid produced by plants growing on rocks
plz give me BRAINLIEST answer
Which of these reservoirs contains the most water?
Answer:
Glaciers
Explanation:
Reservoirs refers to paces where water are stored. The largest water reservoir on earth are the oceans which contain about 97% of all the water on the earth.
The next highest reservoir are the glaciers or the polar ice caps. These hold quite an enormous amount of the water found on earth.
Surface and other fresh water only account for about 1.2% of all the surface water on earth.Ground water accounts for a very minute percentage of the water found on earth.
Density of gold is 19.3g/cm^3 what is the density in lbs/in^3 units
The density in lbs/in³ units : 0.697
Further explanationGiven
Density of gold is 19.3 g/cm³
Required
Conversion to lbs/in³
Solution
Density is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
Density formula:
[tex]\large {\boxed {\bold {\rho ~ = ~ \frac {m} {V}}}}[/tex]
Conversion factor
1 g = 0,00220462 lbs
1 cm³ = 0,0610237 in³
So the density :
[tex]\tt 19.3~\dfrac{g}{1~cm^3}\times \dfrac{cm^3}{0.0610237~in^3}\times \dfrac{0.00220462~lbs}{1~g}=0.697~lbs/in^3[/tex]
Which of the following statements about sidestream smoke is not true?
a. It is the smoke that a smoker inhales from a cigarette.
b. It is dirtier and has a different chemical makeup than mainstream smoke.
c. It is the smoke that people around the smoker inhale.
d. It is the smoke that results from the burning end of a cigarette.
Answer: a
Explanation: the smoker actually exhales the sidestream smoke
I need help with science. picture attached
Answer:
there is no picture.
Explanation:
How many chromium atoms are in 3.56 x 10^-21 moles of potassium chromate?
Answer:
21.44× 10² atoms
Explanation:
Number of chromium atoms = ?
Moles of potassium chromate = 3.56 × 10⁻²¹ mol
Solution:
1 mole of K₂CrO₄ contain 1 mole of Cr.
3.56 × 10⁻²¹ moles of K₂CrO₄ contain 3.56 × 10⁻²¹ moles of Cr.
Number of atoms of Cr:
1 mole contain 6.022× 10²³ atoms
3.56 × 10⁻²¹ mole × 6.022× 10²³ atoms / 1mol
21.44× 10² atoms or 2144 atoms
Which statement best explains why cells separate and expel waste?
Answer:
I would say the 2nd one It helps growth and repair of cells of orgasmsBut your school would probably say the 3rd one It helps remove toxins from the body to maintain homeostasisExplanation:
2. Our cells produce a lot of waste that must be eliminated (excreted) from the body. These residues are called excreta. The residues formed from the chemical reactions that take place inside the cells can be eliminated through:
• of the respiratory system (carbon dioxide)
• skin (sweat)
urinary system (urine)
Our cells expel these substances to maintain the dynamic balance (homeostasis) of our body and promote our well-being.
what is the pressure of the dry gas alone ?
P O₂ = 736.2 torr
Further explanationGiven
P tot=760 torr
P H₂O = 23.8 torr
Required
P gas/O₂
Solution
Dalton's law of partial pressures stated that
the total pressure of a mixture of gases is equal to the sum of the partial pressures of the component gases
Can be formulated:
P tot = P1 + P2 + P3 .... Pn
P tot = P H₂O + P O₂
760 torr = 23.8 torr + P O₂
P O₂ = 760 - 23.8
P O₂ = 736.2 torr
How many Joules of energy are required to boil 350g of water at 100 degrees Celsius?
Answer:
[tex]Q_{vap}=7.90x10^5J[/tex]
Explanation:
Hello!
In this case, since this is the vaporization process of water, we need to keep in mind that the enthalpy of vaporization of this compound is 2.256 kJ/g, for 350 g, we obtain:
[tex]Q_{vap}=m*\Delta H_{vap}\\\\Q_{vap}=350g*2.256\frac{kJ}{g} *\frac{1000J}{1kJ} \\\\Q_{vap}=7.90x10^5J[/tex]
Because the process is carried out at 100 °C, the boiling temperature of water, already.
Best regards!
someone please help me with this vocab
Answer:
1) digestion
2) hydroxide ion
3) neutralization
4) pH scale
5) hydrogen ion
6) chemical digestion
7) mechanical digestion
8) salt
Explanation:
I might be wrong though.
Answer:
1) digestion
2) hydroxide ion
3) neutralization
4) pH scale
5) hydrogen ion
6) chemical digestion
7) mechanical digestion
8) salt
Explanation: I just saw this ik its probably really late but i just decied
to give it a try
The atomic number of an element is ____________________.
a. the number of protons in each atom of the element.
b. 1 mol of the element.
c. the number of neutrons in each atom of the element.
d. the mass of the element.
Answer:
a & b both are correct. But if you want only one answer, then it's 'a'
What is matter? Choose the best answer.
A Anything that is solid
B Anything that takes up space
C Anything that has a fixed volume
D Anything that can be seen
Answer:
B
Explanation:
I NEED HELP REALLY BAD AND THIS IS DUE IN 5 MINSSS
The successive ionization energies for a given element are listed. How many valence electrons does it have?
Answer:
5
Explanation:
The number of valence electrons in the atom is 5 as can be seen from the ionization energy.
Ionization energy is the measure of the readiness of an atom to lose an electron. The lower the value the easier it is for an atom to lose an electron and vice versa.
After the removal of the first electron it becomes increasingly more difficult to remove succeeding electrons because of the imbalance between the positive nuclear charge and the remaining electrons.Therefore, since we have 5 ionization energies given, the number of valence electrons in this atom is 5.
Which is the lowest energy level having “d” orbitals?
Answer:
n=3 the minimum n for which d orbital exist.
Can y’all help me with this question How many atoms are found in the chemical formula below Al2( SiO3)2
Answer:
the answer is 10
Explanation:
Al2 is 2 atoms by itself
(SiO3)2 is 8 because Si is a single atom and O3 is 3 oxygen atoms but because of the subscript outside of the parentheses it doubles and becomes 2 and 6 respectively
! 20 points !need answer FAST!
In nuclear reactions, how can huge amounts of energy be produced?
A. By converting chemical energy into nuclear energy
B. By releasing thermal energy in uranium
C. By creating energy from the surrounding space
D. By destroying matter to create energy
Answer:
C.
Explanation: In nuclear fission and fusion reactions, some of the energy in matter is converted to energy. If you weigh the reactants and the products, the products will weigh less than the reactants. This is called the mass defect and is the result of turning matter into energy.
Answer:
D.
Explanation:
With the Fat Boy and Little Boy nuclear bombs that were drop on Japan, They used a little gun (inside the bomb) that shot a little slug. this hit and caused a chain reaction that caused the bomb to detonate. This released much energy. Destroying much of the two cities when the bombs were dropped.
5. What is the wavelength of a radio station emitting its signal at 95.5 MHz? Estimate your
answer to the nearest power of ten.
Answer:
[tex]\lambda=314\times 10^{-2}\ m[/tex]
Explanation:
Given that,
Frequency, f = 95.5 MHz
We need to find the wavelength of a radio station emitting its signal.
The relation between the frequency and the wavelength is given by :
[tex]c=f\lambda\\\\\lambda=\dfrac{c}{f}\\\\\lambda=\dfrac{3\times 10^8}{95.5\times 10^6}\\\\=3.14\ m[/tex]
or
[tex]\lambda=314\times 10^{-2}\ m[/tex]
So, the wavelength of a radio station is [tex]314\times 10^{-2}\ m[/tex].
When solutions of acetic acid and sodium hydroxide react, which of the following are not present in the net ionic equation?
I. hydrogen ion
II. acetate ion
III. sodium ion
IV. hydroxide ion
A) I and II.
B) I, II, and III.
C) I and IV.
D) I and III.
E) II and III.
Answer:
E) II and III.
Explanation:
Let's consider the complete ionic equation when solutions of acetic acid and sodium hydroxide react. It includes all the ions and molecular species.
CH₃COO⁻(aq) + H⁺(aq) + Na⁺(aq) + OH⁻(aq) ⇒ CH₃COO⁻(aq) + Na⁺(aq) + H₂O(l)
The net ionic equation includes only the ions that participate in the reaction and the molecular species.
H⁺(aq) + OH⁻(aq) ⇒ H₂O(l)
The species not present are:
II. acetate ion
III. sodium ion
What is this element help asap
Explanation:
In this element, there are:
11 protons (in blue)12 neutrons (in red), and11 electrons (in green)We find the element with atomic number 11, which is Sodium. (Na)
Answer: sodium
Explanation:
Which of these pH values indicates a basic solution?
Answer:
The pH scale is often said to range from 0 to 14, and most solutions do fall within this range, although it's possible to get a pH below 0 or above 14. Anything below 7.0 is acidic, and anything above 7.0 is alkaline, or basic.
Explanation:
brainliest plsssssssss
The pH value that indicates a basic solution is if the pH of solution lies between 7 to 14 in the pH scale.
Basic solution is a solution whose pH is more than 7, indicating that it is alkaline or basic in nature. Basic solutions have a lower concentration of hydrogen ions [tex]\rm (H^+)[/tex] than pure water, which has a neutral pH of 7.0.
Basic solutions can be created by dissolving certain salts or bases in water, such as sodium hydroxide (NaOH) or potassium hydroxide (KOH).
Therefore, if the pH of a solution is more than 7 it is said to be basic in nature.
Learn more about basic solution here:
https://brainly.com/question/3449428
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Mass of 2×10^21 number of atoms of an element is 0.4g. What is the mass of 0.5 mole of the element?
Answer:
66.7 g
Explanation:
Number of atoms = 2×10²¹
Mass of 2×10²¹ atoms = 0.4 g
Mass of 0.5 moles of that element = ?
Solution:
1 mole contain 6.022×10²³ atoms
2×10²¹ atoms × 1 mol / 6.022×10²³ atoms
0.33×10⁻² mol
0.003 mol
0.003 mole have mass of 0.4 g
0.5 mol have mass 0.5/0.003×0.4 g = 66.7 g
List 2 types of bacteria
"Spherical: Bacteria shaped like a ball are called cocci, and a single bacterium is a coccus. Examples include the streptococcus group, responsible for “strep throat.”
Rod-shaped: These are known as bacilli (singular bacillus). ...
Spiral: These are known as spirilla (singular spirillus). " - Medical News Today