Answer:
[tex]pH = - log[H {}^{ + } ] \\ 8.8 = - log[H {}^{ + } ] \\ \: [H {}^{ + } ] = {10}^{ - 8.8} \\ [H {}^{ + } ] = 1.585 \times {10}^{ - 9} \: mol {dm}^{ - 3} [/tex]
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
Calculate the mass of hydrogen formed when 26.98 g of aluminum reacts with excess hydrochloric acid according to the following balanced chemical equation: 2 Al + 6 HCl → 2 AlCl3 + 3 H2
Answer: The mass of hydrogen formed when 26.98 g of aluminum reacts with excess hydrochloric acid according to the given balanced equation is 3.03 g.
Explanation:
The given balanced reaction equation is as follows.
[tex]2Al + 6HCl \rightarrow 2AlCl_{3} + 3H_{2}[/tex]
Here, the mole ration of Al and hydrogen produced is 2 : 3
As mass of aluminum is given as 26.98 g. So, moles of aluminum (molar mass = 26.98 g/mol) is as follows.
[tex]Moles = \frac{mass}{molar mass}\\= \frac{26.98 g}{26.98 g/mol}\\= 1 mol[/tex]
So, when 1 mole of Al reacted then 1.5 moles of hydrogen is produced as per the given mole ratio.
Therefore, mass of hydrogen formed is calculated as follows.
[tex]mass = moles \times molar mass\\= 1.5 mol \times 2.02 g/mol\\= 3.03 g[/tex]
Thus, we can conclude that the mass of hydrogen formed when 26.98 g of aluminum reacts with excess hydrochloric acid according to the given balanced equation is 3.03 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!
Look at picture please
Answer:
Keep temperature constant and increase the pressure of the reaction. The rate of reaction increases.
Explanation:
First of all, the question is asking us to design an experiment to investigate the effect of pressure on the rate of reaction hence the pressure can not be held constant since it is the variable under investigation. This eliminates the first option.
Secondly, increasing the pressure of the reaction means that particles of the gas collide more frequently leading to a greater number of effective collisions and a consequent increase in the rate of reaction according to the collision theory.
Hence the answer above.
describe what it would be like to be an atom
Explanation:
An atom consists of two regions. The first is the tiny atomic nucleus, which is in the center of the atom and contains positively charged particles called protons and neutral, uncharged, particles called neutrons. ... Most atoms contain all three of these types of subatomic particles—protons, electrons, and neutrons.
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
1,500 grams is equal to:
1.5 kg
1.5L
1.5 cm
all of the above
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.
Phosphorus -32 is a commonly used radioactive nuclide in biochemical research, particularly in studies of nucleic acids. The half-life of phosphorus-32 is 14.3 days. What mass of phosphorus-32 is left from an original sample of 175 mg of Na332PO4 after 35.0 days
Answer: The mass of P-32 left from the original sample is 32.07 mg
Explanation:
All radioactive decay processes follow first-order reactions.
Calculating rate constant for first order reaction using half life:
[tex]t_{1/2}=\frac{0.693}{k}[/tex] .....(1)
[tex]t_{1/2}[/tex] = half life period = 14.3 days
k = rate constant = ?
Putting values in equation 1:
[tex]k=\frac{0.693}{14.3days}\\\\k=0.0485days^{-1}[/tex]
The integrated rate law equation for first-order kinetics:
[tex]k=\frac{2.303}{t}\log \frac{a}{a-x}[/tex] ......(2)
Given values:
a = initial concentration of reactant = 175 mg
a - x = concentration of reactant left after time 't' = ? mg
t = time period = 35.0 days
Putting values in equation 2:
[tex]0.0485days^{-1}=\frac{2.303}{35.0 days}\log (\frac{175}{a-x})\\\\\log (\frac{175}{a-x})=\frac{0.0485\times 35.0}{2.303}\\\\\log (\frac{175}{a-x})=0.737\\\\\frac{175}{a-x}=10^{0.737}\\\\a-x=\frac{175}{5.457}=32.07mg[/tex]
Hence, the mass of P-32 left from the original sample is 32.07 mg
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
12 + NaF --> Nal + F2 What is the coefficient of Nal when this equation is
balanced? *
Answer:
Explanation:
NaL
Difluorine - F2
Molar Mass Bond Polarity F₂ Fluorine Gas Fluorine
Products
Sodium Fluoride - NaF
Molar Mass Bond Polarity Oxidation State Floridine Sodium Monofluoride Naf
L2
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
Question 13 of 32
The pH of a sample of seawater is 8.0. What is the hydrogen ion concentration of seawater?
A. 8.0 M
B. 1 x 108 M
C. 6.0 M
D. 1 x 10-8 M
Answer:
D
Explanation:
If the initial amount of indium-117 is 5.2 g, how much indium-117 is left in the body after 86 min
Which commercial technology commonly uses plasmas?
a radio
a race car
a television
a microwave oven
Answer:
A television is commercial technology commonly uses plasmas.In which of the following molecules is hydrogen bonding likely to be the most significant component of the total intermolecular forces??
a. C6H13NH2
b. CH3OH
c. CH4
d. C5H11OH
e. CO2
Answer:
The given molecules are:
a. C6H13NH2
b. CH3OH
c. CH4
d. C5H11OH
e. CO2
Explanation:
The hydrogen bond is a weak electrostatic force of attarction that exists between covalently bonded hydrogen (of -OH or -NH2 or HF) with a highly electronegative atom like N,O and F.
Hydrogen bonding is of two types:
Intermolecular hydrogen bond (exists between two molecules)
Intramolecular hydrogen bond(exists within a molecule).
For example intermolecular hydrogen bond in water is shown below:
Among the given options,
a. C6H13NH2 has -NH2 linkage which leads to hydrogen bond formation.
b. CH3OH has -OH bond and it leads to hydrogen bond fomation.
d. C5H11OH has also -OH bond and it leads to hydrogen bond fomation.
Reamining molecules, CH4 and CO2 do not form hydrogen bond.
Hence, answer is:
options a,b,d.
Francine makes several measurements of the mass of a metal block. The data set is shown in the table below.
Measurement
Mass of metal block (g)
1
20.73
2
20.76
3
20.68
4
20.75
After analyzing this data set, Francine calculates a value of 20.73 g.
Which of these characteristics has been calculated?
mean
median
mode
range
Answer:
Mean
Explanation:
The mean of a series of measurements is calculated when all the measurements are added up and then divided by the number of measurements taken, as follows:
Sum of Measurements = 20.73 + 20.76 + 20.68 + 20.75 = 82.92As there are 4 measurements, the mean is:
Mean = 82.92 / 4 = 20.73Answer:
A
Explanation:
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
is it a physical or chemical change when a candle is lit
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 :)
How many grams of Al2O3 is extracted from 250. g of FeO?
Answer:
[tex]m_{Al_2O_3}=118.27gAl_2O_3[/tex]
Explanation:
Hello there!
In this case, if we consider the following chemical reaction, whereby Al2O3 is produced from Al and FeO:
[tex]3FeO+2Al\rightarrow 3Fe+Al_2O_3[/tex]
Thus, since there is 3:1 mole ratio of FeO to Al2O3, it turns out feasible for us to use their molar masses, 71.844 g/mol and 101.96 g/mol respectively, to obtain the grams of the latter as follows:
[tex]m_{Al_2O_3}=250.gFeO*\frac{1molFeO}{71.844gFeO}*\frac{1molAl_2O_3}{3molFeO} *\frac{101.96gAl_2O_3}{1molAl_2O_3}\\\\m_{Al_2O_3}=118.27gAl_2O_3[/tex]
Regards!
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
Which pair of compounds has the same empirical formula?
1.
C2H2 and C6H6
2
C2H6 and C3H8
3.
CH3OH and C2H5OH
4.
CH3CHO and CH3COOH
Explanation:
Correct option is
B
CH
3
COOH
Empirical formula of Glucose C
6
H
12
O
6
= C
1
H
2
O
1
Now, Empirical formula of CH
3
COOH=C
1
H
2
O
1
As empirical formula is the simplest whole number ratio of number of different types of atoms present in the given molecular formula.
the density of gold is 19.3 g/ml. if you had a cube made of pure gold that weighs 58.1 pounds what would be the lengh of a side of this cube
Answer:
11.1 cm
Explanation:
First we convert 58.1 pounds into grams:
58.1 lb * [tex]\frac{453.592g}{1lb}[/tex] = 26353.69 gThen we calculate the volume of the gold cube, using the given density:
26353.69 g ÷ 19.3 g/mL = 1365.48 mL
1365.48 mL is equal to 1365.48 cm³.With the volume of a cube we can calculate the side length:
Length = ∛(1365.48 cm³) = 11.1 cmHow can we protect space shuttles or astronauts from space radiation in the absence of the atmospheric layer?
What is the role of gravity in maintaining the atmospheric layer around the earth ?
Please put your answers with clear explanation.
Thank you !
Answer:Earth's protective magnetic bubble, called the magnetosphere, deflects most solar particles. ... The International Space Station cruises through low-Earth orbit, within Earth's protection, and the station's hull helps shield crew members from radiation too.☘
have a nice day
Can you help ASAP? Thanks you.
Answer:
ok
Explanation:
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
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 element tin has the following number of electrons per shell: 2, 8, 18, 18, 4. Notice that the number of electrons in the outer shell of a tin atom is the same as that for a carbon atom. Therefore, what must be true of tin
The question is incomplete, the complete question is:
The element tin has the following number of electrons per shell: 2.8. 18, 18, 4. Notice that the number of electrons in the outer shell of a tin atom is the same as that for a carbon atom. Therefore, what must be true of tin? Tin is a polar atom and can bind to other polar atoms. Tin has a high molecular weight to give tin-containing molecules greater stabilty. All of the above Tin conform single covalent bonds with other elements, but not double or triple covalent bonds Tincan bind to up to four elements at a time
Answer:
Tin can bind to up to four elements at a time
Explanation:
Certain important points were made in the question about tin and one of them is that tin is an element in the same group as carbon hence it has the same number of valence electrons as carbon.
Carbon is always tetra valent. The tetra valency of carbon is the idea that carbon forms four bonds.
If tin has the same number of valence electrons as carbon, then, tin can bind to up to four elements at a time
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]