Answer:
I want to say 10 grams
Explanation:
80 grams is your start
and a half-life is half of that so...
half of 80 ( and or 80/2)
40 grams
then another half is...
half of 40 (and or 40/2)
20 grams
then another half-life is...
half of 20 (and or 20/2)
10 grams
That is 3 half-life of 80 grams
*becareful not to just divide 80 / 3 you will get 26.666 (repeating) that is incorrect
you want a half of a half of a half
An s orbital has how many orientations? Group of answer choices
Answer:
One orientation
Explanation:
A s orbital is a sphere like shape that surrounds the atomic nucleus that consists of electrons that can be found at the highest or lowest region of the orbital. S orbitals only consist of "one orientation" and is commonly mistaken by the p orbital because the p orbital also consists of electrons that can be found the most.
Hope this helps.
How many moles of Fe2+ are there in a 2.0g sample that is 80% by mass of FeCl2?
The number of moles of [tex]Fe^{2+}[/tex] in the [tex]2.0g[/tex] sample of [tex]FeCl_{2}[/tex] is [tex]0.0157[/tex] moles.
The following points should be noted about the number of moles:
The number of moles of any substance can be calculated using the mass and molar mass of the substance. [tex]n = \frac{mass}{molarmass}[/tex], where n is the number of moles.Mass of the sample given as [tex]2.0g[/tex] and the molar mass of the sample as [tex]126.75g/mol[/tex].
Therefore, the number of moles of [tex]Fe^{2+}[/tex]is obtained by dividing the mass by the molar mass.
Hence the number of moles is obtained as [tex]0.0175[/tex] moles.
Learn more about the number of moles here:
https://brainly.in/question/22534630
6b
Which of the following is a starting compound during
cellular respiration?
Answer: Oxygen and glucose.
Explanation:
Oxygen and glucose are both reactants in the process of cellular respiration. The main product of cellular respiration is ATP; waste products include carbon dioxide and water.Jun 1, 2020
PLEASEEE HELP ?!?!?!
which of the following processes provide evidence of the particulate nature of matter
I. Diffusion
II. Filtration
III. Osmosis
A. I and II only
B. I and III only
C. II and III only
D. I, II and III
Answer:
B
Explanation:
I think the answer is Diffusion and Osmosis
The processes that provide evidence of the particulate nature of matter would be diffusion and osmosis.
Matter is defined as anything with mass/weight and able to occupy space. Matters could be molecules of solid, liquid, or gases. The molecules of each category of matter have their specific characteristics.Molecules of liquids and gases are able to diffuse. Diffusion is defined as the movement of molecules from the region of high concentration to the region of low concentration. Molecules of solids in the dissolved form are also able to diffuse. Water molecules are also able to move from the region of high to the region of low water potentials by osmosis in the presence of a semi-permeable membrane.Thus, both diffusion and osmosis back up the particulate nature of matter.
More on the particulate nature of matter can be found here: https://brainly.com/question/15230454?referrer=searchResults
which 2 not one 2! hjmdnxhjund
Answer:
A and D then I guess
Explanation:
sorry hope this helps!
Giselle is working with a chemical substance in a laboratory. She observes that when the chemical is heated, it gives off a gas. She assumes that the gas is oxygen but decides to test this assumption to verify it. Which type of scientific knowledge is Giselle’s assumption? A. fact B. hypothesis C. law D. observation E. theory
Answer:
The correct answer is B. Hypothesis
Explanation:
Please help will give brainliest
Answer:
the answer id D
Explanation:
i dont know im just living here 5
Which three are advantages of asexual reproduction?
A:Offspring are more likely to survive environmental changes.
B:Some offspring are more likely to survive a disease.
C:Less energy is required to reproduce.
D:The population can increase from only one parent.
E:The population can increase quickly.
Answer:
sorry if I get this wrong I think it is C
Explanation:
Potassium Phthalate, KC8H604, is a main source of whistle fuel for many fireworks. A standard firework had 25g of potassium phthalate. Calculate the following:
The molar mass of the compound.
How many molecules of fuel there are
The number of moles of Carbon
Answer:
Explanation:
The given compound is:
KC₈H₆O₄
Mass of the compound = 25g
Molar mass of the compound
KC₈H₆O₄
Atomic mass of K = 39
C = 12
H = 1
O = 16
Molar mass of the compound = 39 + 8(12) + 6 (1) + 4(16)
= 205g/mol
Number of molecules of fuel there in:
Find the number of moles then convert this to number of molecules;
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
Number of moles = [tex]\frac{25}{205}[/tex] = 0.12mol
1 mole of a compound contains 6.02 x 10²³ molecules
0.12 mole of the phthalate will contain 0.12 x 6.02 x 10²³ =
7.34 x 10²²molecules
Number of moles of Carbon
1 mole of the phthalate contains 8 mole of carbon
0.12 mole of the phthalate will contain 0.12 x 8 = 0.96mole of carbon
Determine the pH of a 2.0 x 10-2 M Sr(OH)2 solution.
pH of the Sr(OH)₂ solution : 12.6
Further explanationpH is the degree of acidity of a solution that depends on the concentration of H⁺ ions. The greater the value the more acidic the solution and the smaller the pH.
pH = - log [H⁺]
Sr (OH) ₂ solution is a base with valence 2, so we determine the pOH from the OH ion concentration - which is expressed by pOH = - log [OH -]. After that we determine the pH value from the relationship:
[H⁺] [OH⁻] = Kw=10⁻¹⁴
pH + pOH = 14
Sr(OH)₂⇒Sr²⁺+2OH⁻
From equation [Sr(OH)₂] : [OH⁻]=1 : 2, so [OH⁻]=
[tex]\tt [OH^-]=2\times 2.10^{-2}=4.10^{-2}~M[/tex]
[tex]\tt pOH=-log[OH^-]\\\\pOH=-log~4.10^{-2}\\\\pOH=2-log~4\rightarrow 1.398 \\\\pH+pOH=14\\\\pH=14-1.398\\\\pH=12.6[/tex]
pH is the measurement of the concentration of hydrogen or hydronium ion in an aqueous solution. The pH of strontium hydroxide is 12.6.
What is pH?The pH is the potential of hydrogen or the negative log of its concentration.
First, calculate the pOH of strontium hydroxide by:
[tex]\begin{aligned} \rm pOH &= \rm - log [OH ^{-}]\\\\&= \rm -log [4\times10^{-2}]\\\\&= 1.398\end{aligned}[/tex]
Now, calculate pH from pOH as:
[tex]\begin{aligned}\rm pH &= 14 - \rm pOH\\\\&= 14 - 1.398\\\\&= 12.6\end{aligned}[/tex]
Therefore, 12.6 is the pH of strontium hydroxide.
Learn more about pH here:
https://brainly.com/question/10725749
A biochemist carefully measures the molarity of magnesium ion in of cell growth medium to be . Unfortunately, a careless graduate student forgets to cover the container of growth medium and a substantial amount of the solvent evaporates. The volume of the cell growth medium falls to . Calculate the new molarity of magnesium ion in the cell growth medium. Be sure your answer has the correct number of significant digits.
Answer:
760 uM
Explanation:
A biochemist carefully measures the molarity of magnesium ion in 47, mL of cell growth medium to be 97 uM. Unfortunately, a careless graduate student forgets to cover the container of growth medium and a substantial amount of the solvent evaporates. The volume of the cell growth medium falls to 6.0 mL. Calculate the new molarity of magnesium ion in the cell growth medium Be sure your answer has the correct number of significant digits.
The problem here is that the amount of magnesium ion remains the same irrespective of the volume.
Amount of magnesium in the growth medium = molarity x volume
= 97 x [tex]10^{-6}[/tex] x 47 x [tex]10^{-3}[/tex] = 4.559 x [tex]10^{-6}[/tex]
Then, the volume reduced to 6.0 mL, the new molarity becomes;
molarity = mole/volume
= 4.559 x [tex]10^{-6}[/tex]/6 x [tex]10^{-3}[/tex] = 7.598333 x [tex]10^{-4}[/tex] M = 759.83333 uM
To the correct number of significant digits = 760 uM
Describe how the periodic
table is organized and how
that organization increases
its usefulness (hint: think
about how the position of an
element in the table matters)
Answer:
Elements in the periodic table are arranged according to the increasing atomic number.
We can predict the chemical properties of an element by looking at it's position in the periodic table.
Which pair of elements will form a covalent bond? A. Aluminium and Chlorine B. Carbon and Sulfur C. Lithium and Oxygen D. Potassium and Chlorine
Explanation:
Aluminum and chlorine form covalent bond.
Therefore,
Option A is correct✔
What is electronegativity?
Explain the periodic trend -
what is it, why is it that way
Answer:
Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons. The Pauling scale is the most commonly used. Fluorine (the most electronegative element) is assigned a value of 4.0, and values range down to caesium and francium which are the least electronegative at 0.7.
Explanation:
Major periodic trends include: electronegativity, ionization energy, electron affinity, atomic radius, melting point, and metallic character. ... These trends exist because of the similar atomic structure of the elements within their respective group families or periods, and because of the periodic nature of the elements
If I Gave A Pig Bacon Would He Eat It ?
The concentration of CI ion in a sample of H,0 is 15.0 ppm. What mass of CI ion is present in 240.0 mL of H,0, which has a density of 1.00 g/mL?
Answer:
Mass of solute = 0.0036 g
Explanation:
Given data:
Concentration of Cl⁻ = 15.0 ppm
Volume of water = 240 mL
Mass of Cl⁻ present = ?
Solution:
1 mL = 1 g
240 mL = 240 g
Formula:
ppm = mass of solute / mass of sample ×1,000,000
by putting values,
15.0 ppm = (mass of solute / 240 g) ×1,000,000
Mass of solute = 15.0 ppm × 240 g / 1,000,000
Mass of solute = 0.0036 g
Please help Fast i dont Know
When the volume of a gas is
changed from 3.6 L to 15.5 L, the
temperature will change from
°C to 87°C.
Assume that the number of moles and the
pressure remain constant.
Be sure to notice that temperatures are
given in °C!
Initial temperature = -189.4 °C
Further explanationGiven
the volume of a gas is changed from 3.6 L to 15.5 L
final temperature = 87 °C = 87+ 273 = 360 K
Required
initial temperature
Solution
Charles's Law
When the gas pressure is kept constant, the gas volume is proportional to the temperature
[tex]\tt \dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}[/tex]
[tex]\tt T_1=\dfrac{V_1.T_2}{V_2}\\\\T_1=\dfrac{3.6\times 360}{15.5}\\\\T_1=83.6~K=-189.4^oC[/tex]
Based on the chemical equation, use the drop-down menu to choose the coefficients that will balance the chemical equation:
(
)BaO2 + (
)H2SO4 → (
)H2O2 + (
)BaSO4
Answer:
1
1
1
1
Explanation:
the equation is balancing
For the reaction below, if the rate of appearance of Br2 is 0.180 M/s, what is the rate of disappearance of
NOBr?
2 NOBr(g) → 2 NO(g) + Br2(g)
a. –0.360 M/s
b. –0.090 M/s
c. 0.090 M/s
d. 0.180 M/s
e. 0.720 M/s
Answer:
–0.360 M/s
Explanation:
Based on the principle of complementary colors, which colors or wavelengths of light would you expect to be most strongly absorbed by Cu2 ions?
Answer:
Red and Orange
Explanation:
Complementary colors are those colours located across from each other on a color wheel. If we look at the colour wheel attached to this answer, we will see various complementary colours shown.
A good look at the attached colour wheel reveals that blue Cu2+ ions absorbs light around the red and orange portions of the visible spectrum.
Will give brainliest
Answer:
C
Explanation:
The concept behind, is mole ratio of Al:FeO
velocity is a ______ quantity
Answer:
vector quantity
Explanation: Brainliest pls
Atoms of the same element can have different properties. ( true or false )
Answer:
Atoms of the same element have the same chemical properties. The only differences between atoms of the same element are the number of neutrons in the nucleus and the atomic weight of each isotope. false
Answer:
False
Explanation:
Different elements can have different properties, but not atoms of the same element
Which elements are considered metals? Non-metals? Metalloids?
The answer is in the photo.
Pieces of DNA that pass genetic traits from parent to offspring
A. Phenotype
B. Gene
D. Allele
Answer:
gene
Explanation:
True or False: Most metals are found to occur naturally in their uncombined states.
Answer:
I think it's true. But I'm not sure
Answer:
True
Explanation:
Plz help
Plz and thank u
please help me i will give brain list
Answer:
a. pentane = C5H12
b. Heptane = C7H16
c. Hexyne = C6H10
d. Octene = C8H16
e. Nonane = C9H20
Hope it helps.
1-pentene
Molecular Formula C5H10
Condensed Structural FormulaCH2=CH(CH2)2CH3
Melting Point (°C)–138
Boiling Point (°C)30
2- heptane is the straight-chain alkane with the chemical formula H3C(CH2)5CH3 or C7H16, and is one of the main components of gasoline (petrol).
which group or groups of atoms are the only atoms with f orbitals?
Answer:
Lanthanides and Actinides
Explanation: