Answer:
Strontium - 38 (atomic #)
Explanation:
An ion with 38 protons, 36 electrons, and 40 electrons is Strontium. Strontium's atomic number is 38.
is it a physical or chemical change when a candle is lit
At STP, which gaseous sample has the same number
of molecules as 5.0 liters of O2 (g)?
A) 6.0 L of F2 (g)
B) 4.5 L of O2 (g)
C) 3.0 L of H2 (g)
D) 5.0 L of Cl2 (9)
What is the mass of NaCl required to make 150 grams of a 12% solution of NaCl in water? (5 points)
a
13 grams
b
18 grams
c
22 grams
d
32 grams
Answer:
18 grams
Explanation:
Mass of solution = 150 g
Percent concentration = 12%
Percent concentration = mass of solute/mass of solution × 100
Let the mass of solute be x
12= x/150 × 100
12= 100x/150
12 × 150 =100x
x= 12 × 150/100
x = 18 g
Answer:
18
Explanation:
Mass of solution = 150 g
Percent concentration = 12%
Percent concentration = mass of solute/mass of solution × 100
Let the mass of solute be x
12= x/150 × 100
12= 100x/150
12 × 150 =100x
x= 12 × 150/100
x = 18 g
As a result of the particles in a gas being in constant motion, gas has a _______.
variable volume
variable Pressure
variable Shape
variable mass
Answer:
i think it's variable pressure
if not soo advance sorry :)
2KClO3 (s)⇄2KCl (s)+ 3O2 (aq) equilibrium constant
Answer: The equilibrium constant for the given chemical reaction is [tex][O_2]^3[/tex]
Explanation:
The equilibrium constant is defined as the ratio of the concentration of the products to the concentration of reactants each raised to the power of their stoichiometric coefficients.
The concentration of all the solids and liquids are considered to be 1 in the expression of equilibrium constant
For the given chemical equation:
[tex]2KClO_3(s)\rightleftharpoons 2KCl(s)+3O_2(aq)[/tex]
The expression of equilibrium constant follows:
[tex]K_{eq}=[O_2]^3[/tex]
Hence, the equilibrium constant for the given chemical reaction is [tex][O_2]^3[/tex]
A sample of gas has a volume of 100. L at 17 °C and 800. torr. To what temperature must the gas be cooled in order for its volume to become 50.0 L at a pressure of 600. torr? Your answer will need to be in Kelvin.
Source
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Answer:
108.81 K
Explanation:
First convert 17 °C to Kelvin:
17 + 273.16 = 290.16 KAssuming ideal behaviour, we can solve this problem by using the combined gas law, which states that at constant composition:
P₁V₁T₂=P₂V₂T₁Where in this case:
P₁ = 800 torrV₁ = 100 LT₂ = ?P₂ = 600 torrV₂ = 50 LT₁ = 290.16 KWe input the data:
800 torr * 100 L * T₂ = 600 torr * 50 L * 290.16 KAnd solve for T₂:
T₂ = 108.81 KUse the following key to classify each of the elements below in its elemental form:
A. Discrete atoms ...
B. Molecules ...
C. Metallic lattice
D. Extended, three-dimensional network
1. Argon
2. Bromine
3. Nitrogen
4. Fluorine
Answer:
Discrete atoms
Argon
Molecules
Bromine
Nitrogen
Fluorine
Explanation:
The existence of substances in the elemental form depends on the nature of the substance.
Argon is a noble gas hence it seldom participates in chemical combination therefore it exists as discrete molecules in elemental form.
Bromine, fluorine and nitrogen all exist as diatomic gases because they combine readily with each other to form elemental molecules. An elemental molecule is a molecule composed of the atoms of the same element.
Which of the following is key to generating a bell curve?
An aqueous sucrose (C12H22O11) solution must be created for an experiment. If 100.00 mL of 0.200 M solution is needed, what amount of sucrose (in grams) must be weighed out
Answer:
6.85 g
Explanation:
Step 1: Given data
Molar concentration of the solution: 0.200 M (0.200 mol/L)Volume of the solution: 100.00 mL (0.10000 L)Step 2: Calculate the moles of sucrose (solute) required
Molarity is equal to the moles of solute divided by the liters of solution.
M = moles of solute / liters of solution
moles of solute = M × liters of solution
moles of solute = 0.200 mol/L × 0.10000 L = 0.0200 mol
Step 3: Calculate the mass corresponding to 0.0200 moles of sucrose
The molar mass of sucrose is 342.3 g/mol.
0.0200 mol × 342.3 g/mol = 6.85 g
The amount of sucrose (in grams) must be weighed out for the given reaction is 6.846g.
How we calculate mass from moles?Mass of any substance will be calculated by using the moles as:
n = W/M, where
W = required mass
M = molar mass
Given that, molarity of sucrose = 0.2 M
Volume of solution = 100mL = 0.1 L
Relation between moles and molarity is represented as:
M = n/V
On putting values on the above equation we get,
n = (0.2)(0.1) = 0.02 moles
We know that molar mass of sucrose (C₁₂H₂₂O₁₁) = 342.3 g/mole
Now we calculate the required mass by putting values on the first equation as:
W = (0.02)(342.3) = 6.846g
Hence, the required mass of sucrose is 6.846g.
To know more about moles, visit the below link:
https://brainly.com/question/24639749
Reactants which do not continue to completion are called reactants
state the purpose of Watson and crick DNA structure experiment
Answer:
In Watson and Crick's model, the two strands of the DNA double helix are held together by hydrogen bonds between nitrogenous bases on opposite strands. Each pair of bases lies flat, forming a "rung" on the ladder of the DNA molecule.
Explanation:
hope it helps ya
How many moles of aluminum oxide are produced according to the reaction below given that you start with 40.0 grams of Al and 19.0 grams of O2?
Reaction: 4Al + 3O2 --> 2Al2O3
A. 0.185
B. 0.741
C. 5.00
D. 0.396
From the stoichiometry of the reaction, 0.74 moles of aluminium oxide is produced.
The equation of the reaction is;
4Al + 3O2 --> 2Al2O3
Number of moles of Al = 40.0/27 g/mol = 1.48 moles
Number of moles of O2 = 19.0 g/32 g/mol = 0.59 moles
Now;
4 mols of Al reacts with 3 moles of O2
1.48 moles of Al reacts with 1.48 moles × 3 moles/4 mols
= 1.11 moles
We can see that O2 is the reactant in excess.
Hence;
4 moles of Al produces 2 moles of aluminium oxide
1.48 moles of Al produces 1.48 moles × 2 moles/4 moles = 0.74 moles of aluminium oxide
Learn more about stoichiometry: https://brainly.com/question/9743981
Why is blood considered a suspension?
Answer:
Because platelets and other things are "suspended" in the plasma.
Explanation:
When blood is put into a centrifuge it separates into its separate components (eg: Red blood cells, plasma, White blood cells, platelets, etc)
When 20 grams of KCIO3, is dissolved in 100 grams of water, the solution can be
described as.............if the solubility equals 53.3g/100g H20.
a. Saturated
c. supersaturated
b. unsaturated
d. concentrated
Answer:
b. unsaturated .
Explanation:
Hello there!
In this case, according to the given information, it turns out necessary for us to bear to mind the definition of each type of solution:
- Supersaturated solution: comprises a large amount of solute at a temperature at which it will be able to crystalize upon standing.
- Unsaturated solution: is a solution in which a solvent is able to dissolve any more solute at a given temperature.
- Saturated solution can be defined as a solution in which a solvent is not capable of dissolving any more solute at a given temperature.
In such a way, since 20 grams of the solute are less than the solubility, we infer this is b. unsaturated, as 33.3 grams of solute can be further added to the 100 grams of water.
Regards!
If a solid line represents a covalent bond and a dotted line represents intermolecular attraction, which of the choices shows a hydrogen bond?
1. H−H
2. H4C⋯H−F
3. H3N⋯H−O−H
4. H2O⋯H−CH3
Answer:
3
Explanation:
Hydrogen bonding occurs between molecules in which hydrogen is bonded to a highly electronegative atom such as nitrogen, oxygen, chlorine, etc.
In option 3, the two compounds are H3N and H2O. In both molecules, hydrogen is directly attached to highly electro negative atoms(nitrogen and oxygen respectively). Hence, it is only in option 3 that we observe hydrogen bonding.
Its Acutally A Because if you use the type he used its not even the question
Explination
Im RIght
How is a bacterium cell different from a human cell?
Answer:
Human cells are eukaryotic which means they are more complicated, bacteria cells are prokaryotic which means they are simpler
Explanation:
Hope this helps
help me plsssssssss.... im timed
Answer:
a
Explanation:
a
Answer:
B. Isotopes of the element.
Explanation:
Isotopes are basically atoms of the same element that contain the same number of protons, but a different number of neutrons.
How much energy is released when 2.25kg of water cools from 99.5°C to 4.2°C? 1000g=1kg; 1000J=1kJ; specific heat of water 4.184J/g°C. q=mc∆T
Answer:
897154.2 J
Explanation:
Applying,
q = mcΔT.............. Equation 1
Where q = amount of energy released, m = mass of water, c = specific heat capacity of water, ΔT = Change in temperature
From the question,
Given: m = 2.25 kg = 2250 g, c = 4.184 J/g°C, ΔT = (4.2-99.5) = -95.3°C
Substitute these values into equation 1
q = 2250(4.184)(-95.3)
q = -897154.2 J
q =
Hence the amount of heat released is 897154.2 J
how many moles of H2o are equivelant to 97.3g h2o
Answer:
Number of mole in H2O = 5.4 moles
Explanation:
Given:
Mass of H2O = 97.3 gram
Find:
Number of mole in H2O
Computation:
We know that molar mass of H2O = 18 g/mole
So,
Number of mole = Given Mass / Molar mass
Number of mole in H2O = Mass of H2O / Molar mass of H2O
Number of mole in H2O = 97.3 / 18
Number of mole in H2O = 5.4055
Number of mole in H2O = 5.4 moles
When sugar is added to a sugar solution, the sugar dissolves. Which term
describes the original sugar solution?
A. Saturated
B. Unsaturated
C. Supersaturated
D. Pseudosaturated
SUBMIT
Answer:
the answer is b,.........
Answer:
Unsaturated
Explanation:
Two planets have similar masses but differ in their distances from the Sun.
Which planet experiences a greater gravitational force with the Sun?
A. The planet that is smaller in volume
B. The planet that is larger in volume
C. The planet that is farther from the Sun
D. The planet that is closer to the Sun
Answer:
D. The planet that is closer to the Sun
Upon decomposition, a sample of sodium bicarbonate produces 0.0118 g of sodium carbonate, Na2CO3. How many grams of water does it produce
Answer:
2.00 × 10⁻³ g
Explanation:
Step 1: Write the balanced decomposition reaction
2 NaHCO₃ ⇒ Na₂CO₃ + CO₂ + H₂O
Step 2: Calculate the moles corresponding to 0.0118 g of Na₂CO₃
The molar mass of Na₂CO₃ is 105.99 g/mol.
0.0118 g × 1 mol/105.99 g = 1.11 × 10⁻⁴ mol
Step 3: Calculate the moles of H₂O produced with 1.11 × 10⁻⁴ moles of Na₂CO₃
The molar ratio of Na₂CO₃ to H₂O is 1:1. The moles of H₂O produced are 1/1 × 1.11 × 10⁻⁴ mol = 1.11 × 10⁻⁴ mol.
Step 4: Calculate the mass corresponding to 1.11 × 10⁻⁴ moles of H₂O
The molar mass of H₂O is 18.02 g/mol.
1.11 × 10⁻⁴ mol × 18.02 g/mol = 2.00 × 10⁻³ g
2. Which of the following equations represents a neutralization reaction?
a. H2CO3 + H2O + CO2
b. 2H2O2 → 2H2O + O2
c. Ba(NO3)2 + K2CO3 →
BaCO3 + 2KNO3
d. HNO3 + NaOH → NaNO3 + H2O
Answer:
d. HNO3 + NaOH → NaNO3 + H2O
Explanation:
Hello there!
In this case, according to the given chemical reactions, it turns out necessary for us to recall the definition of neutralization reaction as those whereby an acid reacts with a base, that is why a, b and c are not within the aforementioned description.
In such a way, we infer the reaction is d. HNO3 + NaOH → NaNO3 + H2O since HNO3 is the acid and NaOH the base.
Regards!
Iodine-131 is administered orally in the form of NaI(aq) as a treatment for thyroid cancer. The half-life of iodine-131 is 8.04 days. If you begin with 34.7 mg of this isotope, what mass remains after 8.52 days have passed
Answer:
16.6 mg
Explanation:
Step 1: Calculate the rate constant (k) for Iodine-131 decay
We know the half-life is t1/2 = 8.04 day. We can calculate the rate constant using the following expression.
k = ln2 / t1/2 = ln2 / 8.04 day = 0.0862 day⁻¹
Step 2: Calculate the mass of iodine after 8.52 days
Iodine-131 decays following first-order kinetics. Given the initial mass (I₀ = 34.7 mg) and the time elapsed (t = 8.52 day), we can calculate the mass of iodine-131 using the following expression.
ln I = ln I₀ - k × t
ln I = ln 34.7 - 0.0862 day⁻¹ × 8.52 day
I = 16.6 mg
How long does it take for water to boil?
Answer:
around 5-10 minutes it may take but the actual answer is when the temperature of water reaches 100°Celsius
Answer:
How Long Does It Take to Boil Water? To boil 1 liter of water (4 cups), it takes about 8 to 10 minutes in a pot on the stove with high heat and the lid on. 1 liter of water boils in an electric kettle in about 4 to 5 minutes. 1 liter of water boils in a microwave in about 3 to 4 minutes
have a great day
#brainlestDescribe how the accessory organs of the mouth - tongue, teeth, and saliva - aid in both MECHANICAL and CHEMICAL digestion.
Answer:
Look Below
Explanation:
In terms of mechanical digestion, the teeth provide grinding and tearing motion to break down the food into physically smaller pieces the tongue assists the teeth by moving itself and food around the mouth. In terms of chemical digestion, salivary glands in the back of the tongue and the lower mouth release saliva as a method of adding liquid to the food to help the process of swallowing. In addition, saliva contains the enzyme amylase which helps process some starches into more simple sugars.
What type of reaction is rusting?
O A. Decomposition
O B. Double-displacement
O C. Single-displacement
OD. Oxidation-reduction
What is homeostasis?
a.
production of urine.
b.
maintaining a stable internal environment.
c.
excretion of waste materials.
d.
none of the above.
Please select the best answer from the choices provided
Answer:
the tendency toward a relatively stable equilibrium between interdependent elements, especially as maintained by physiological processes.
Explanation:
A molecule of composition is replicated in a solution containing unlabeled (not radioactive) GTP, CTP, and TTP plus adenine nucleoside triphosphate with all its phosphorus atoms in the form of the radioactive isotope 32P. Will both daughter molecules be radioactive
Answer:
Please find the complete question in the attached file.
Explanation:
It would only be radioactive if the DNA molecule that employed the poly-T rand as templates. Its other molecule of the daughter would not have been radioactive as it did not need dATP for its replication. While each strand of the second molecule includes t, simultaneous reproduction dATP from both daughter molecules is needed so that each of those is radioactive.
The maximum number of moles of compound E that may be formed in the following reaction is: ЗА + 5B + c 个 2E Initial moles: n(A)=0.20 n(B)=0.30 n(C)=0.10
Answer:
E=1.1
Explanation:
let's consider moles of E is X
3(0.20)+5(0.30)+0.10 =2X
2.2=2X
x=1.1
