URGENT which statement describes a chemical property of hydorgen gas
1. Hydrogen gas is colorless
2. Hydrogen gas burns in the air
3.Hydrogen gas has a density of .00000009 gcm3
4. Hydrogen gas has a boiling point of 20k at standard pressure
The chemical property of hydrogen gas is that it burns in the air.
• The lightest element is hydrogen, it can explode at concentrations ranging from 4 to 75 percent by volume in the existence of a flame, sunlight, or a spark.
• One of the prime chemical properties of hydrogen gas is that it is highly flammable and can burn in air at a very broad array of concentrations that is between 4 to 75 percent by volume.
• Some of the physical properties of hydrogen gas are that it is colorless, odorless, nonmetallic, non-toxic, exhibits a density of 0.09 grams per liter, and has a boiling point of -252.87 degree C or 20 K at standard pressure.
Thus, of the mentioned statements, option 2 is correct, that is, the chemical property of hydrogen gas is that it burns in the air.
To know more about:
https://brainly.com/question/22576640
Oda gas is moved from a large container to a small container but it’s temperature and number of moles remain the same, what would happen to the pressure of the gas?
A) it would increase
B) it would be halved
C) it would stay the same
D) it would slightly decreases
Answer is: A) it would increase .
Boyle's Law (the pressure-volume law): volume of a given amount of gas held at constant temperature varies inversely with the applied pressure when the temperature and mass are constant.
p₁V₁ = p₂V₂ (the product of the initial volume and pressure is equal to the product of the volume and pressure after a change).
For example:
p₁ = 1.2 atm; starting pressure.
V₁ = 2.0 L., starting volume.
V₂ = 1.0 L; final volume, smaller than starting volume.
p₂ = ?; final pressure.
1.2 atm · 2 L = p₂ · 1 L.
p₂ = 1.2 atm · 2 L / 1 L.
p₂ = 2.4 atm.
When volume goes up, pressure goes down.
When volume goes down, pressure goes up.
Which of the following are major influences on weather and climate? I. the cycling of water in and out of the atmosphere II. the physical weathering of rocks and soil III. uneven heating of the Earth by the Sun's energy IV. global patterns of atmospheric movement A. I, III, and IV only B. I, II, and IV only. C. I, II, and III only D. II, III, and IV only
A. I, III, and IV only.
Answer:
A. I, III, and IV only
Explanation:
The cycling of water in and out of the atmosphere is an important determinant of weather and climate. Changes in humidity and average rainfall usually depend on this factor.
Uneven heating of the earth by the sun also creates unique patterns of changes in weather and climatic conditions around the world.
Global patterns of atmospheric movement affect parameters such as wind speed etc.
A false statement concerning matter is: Matter cannot be subdivided. Matter is composed of many small particles called atoms. Matter is mostly empty space. All matter contains mass.
Answer:
A) Matter cannot be subdivided.
Explanation:
Hope this comes to your aid.
Matter are anything that is made up of atoms. The quantity of matter can be observed only on the basis of mass and volume calculation. Therefore, the incorrect statement is matter cannot be subdivided.
What is matter?Matter is a substance that has some mass and can occupy some volume. The matter is mainly used in science. Matter can be solid, liquid or gas.
Matter is anything that is made up of atoms. Anything around us that can be physically seen and touched are matter. Ice, water and water vapors are example of matter.
So as we saw that matter has some mass so mass can be measured in gram only. Mass can also be represented as number of molecules. We also saw that matter occupy some volume and that volume is measured only in liter. Degree of Celsius is used to measure temperature which has nothing to do with matter.
Therefore, the incorrect statement is matter cannot be subdivided.
To learn more about matter, here:
https://brainly.com/question/4562319
#SPJ2
kilograms represented by the mass defect for thorium -234=3.09x 10-27 kg what is the nuclear binding energy for thorium -234
Mass defect and binding energy are related as
ΔE = Δmc^2
Where
ΔE = binding energy
Δm = mass defect
c = speed of light
given
mass defect = 3.09x 10-27 kg
We know that speed of light = 3 X 10^8 m /s
ΔE = 3.09x 10-27 kg (3 X 10^8 m /s)^2 = 2.781 X 10^-10 J / Kg
.
.
Answer:
A
Explanation:
2.78 × 10-10 J Is the answer
Physical and chemical change
Chemical change: a change that occurs when one substance combines with another substance to make a new substance
Physical change: a change to any physical property of a substance
Select the electron domain geometry and the molecular geometry for an ammonia molecule, NH3. Check all of the boxes that apply. You may use the periodic table if needed.
trigonal-planar electron domain geometry
trigonal-planar molecular geometry
trigonal-pyramidal electron domain geometry
trigonal-pyramidal molecular geometry
tetrahedral electron domain geometry
tetrahedral molecular geometry
The correct answer is option 4 and 5.
The electron domain geometry for an ammonia molecule, NH₃ has tetrahedral electron domain geometry. In NH₃ there are three bond pair electrons and one lone pair electron. Therefore, NH₃ has four electron pairs which are distributed in a tetrahedral shape.
The molecular geometry for an ammonia molecule, NH₃ is trigonal-pyramidal molecular geometry. Ammonia has one lone pair of electron and three bond pairs of electrons thus the resulting molecular geometry is trigonal-pyramidal.
For an ammonia molecule, the electron domain geometry is tetrahedral, and the molecular geometry is trigonal pyramidal. Therefore, the fourth and fifth option is correct.
The electron domain geometry describes the arrangement of electron domains around the central atom, where an electron domain can be a bond or a lone pair of electrons.
Molecular geometry refers to the arrangement of atoms in a molecule, considering both the bonding and nonbonding electron pairs.
In ammonia, the three hydrogen atoms are bonded to the central nitrogen atom, and the nitrogen atom has one lone pair of electrons.
To learn more about electron domain geometry, follow the link:
https://brainly.com/question/30461548
#SPJ6
Please help with this question:)
The first step is canceling out the like term, in this case it is the atoms and mole specification. I use e instead of multiplying times 10 to a power, it is mostly used in higher sciences but I think it is easier and it is in most calculators. So your equations is 7.43e22 Mg multiplied by (1/6.02e23) multiplied by (24.30) Mg. So all together it is 7.43e22 (1/6.02e23) (24.30). Then just multiply across, it is easier to break it up. 7.43e22 times (1/6.02e23)= .1234219269. Take that and multiply it by 24.30. So that looks like (0.1234219269)x(24.3)= 2.999152824. So if it would be 2.9992 grams of Mg.
Name everyday objects where insulation is used to keep objects warm or cool.
If you answer this question you are a angle confirmed.
Coffee thermos- Maintains heat in the thermos through insulation
Kitchen Appliances- Applicances such as refrigerators keep items cool, while toasters and pots are used to heat items up
Lunchbox- Many lunchboxes are insulated with materials that enables the box to keep cool.
Study the following reaction carefully. What classification should this reaction have? 4Al + 3O 2 2Al 2 O 3
The reaction is a synthesis…
[tex]4Al + 3O_2 \longrightarrow 2Al_2O_3\\[/tex]
… because two substances are combining to make one other substance.
[tex]4\stackrel{\hbox{0}}{\hbox{Al}} + 3\stackrel{\hbox{0}}{\hbox{O}}_2 \longrightarrow 2\stackrel{\hbox{+3}}{\hbox{Al}}_2\stackrel{\hbox{-2}}{\hbox{O}}_3\\[/tex]
It is also a reduction-oxidation reaction because the oxidation number of Al increases from 0 to +3 and the oxidation number of O decreases from 0 to -2.
Which characteristic is typical of metals?
Answer:
Metals are malleable.
Explanation:
The metals are the substances possessing an abundant amount of electrons. They are placed majorly on the left side of the periodic table. The metals are considered as the good conductors of electricity and heat, they are lustrous in appearance, and usually have a high melting point. However, the main property, which distinguishes it from other substances is that they are malleable and ductile, that is, they can be transformed into wires and thin sheets.
What is an ephemeral stream?
A. One that is formed only from chemical weathering
B. One that flows only after rainfall
C. One that is formed only from mechanical weathering
D. One that flows only in flat lands
The correct answer is option B.
An ephemeral stream is one that flows only after rainfall.
Ephemeral streams only exist for a short period of time. They are often found in the desert landscape. Desert climate is arid with sparse to no vegetation. Without plants in the soil, rain water does not get absorbed, and so after rainfall excess water flow as ephemeral streams.
B. An ephemeral stream is one that flows only after rainfall
Using the Mohs standard hardness scale, which of the following scratch tests is correct? Scale Mineral 10 diamond 9 corundum 8 topaz 7 quartz 6 feldspar 5 apatite 4 fluorite 3 calcite 2 gypsum 1 talc Talc scratches calcite. Quartz scratches corundum. Fluorite scratches feldspar. Topaz scratches quartz.
Topaz scratches quartz
Answer:
The correct answer is :'Topaz scratches quartz'.
Explanation:
Mohs scale is a qualitative scale to analyse and characterize scratch resistance of minerals.Harder mineral will easily scratch softer mineral.
Lower value on the scale indicates that mineral can be easily scratched by the another mineral with higher scale value. In other words calcite with scale value of 3 can easily scratch gypsum and talc with scale value of 2 and 1 respectively.
So, from the given options the correct test is that topaz scratches quartz.
A first-order reaction has a half-life of 16.7 s . How long does it take for the concentration of the reactant in the reaction to fall to one-fourth of its initial value?
It takes 33.4 s for the concentration of A to fall to one-fourth of its original value.
A half-life is the time it takes for the concentration to fall to half its original value.
Assume the initial concentration is 1.00 mol/L. Then,
[tex]\text{1.00 mol/L }\stackrel{\text{1st half-life }}{\longrightarrow}\text{ 0.50 mol/L } \stackrel{\text{ 2nd half-life }}{\longrightarrow}\text{0.25 mol/L}\\[/tex]
The concentration drops to one-fourth of its initial value in two half-lives.
∴ Time = 2 × 16.7 s = 33.4 s
Transition metals in the fourth period fill the __________ orbital. A) 3d B) 3p C) 4s D) 4f
I am pretty sure the answer is C, but I am not certain.
The correct answer is A.) 3d
Please do question 13 and 14
13. Bilateral. If it were to split up, it would create an equal two sides.
14. Since the butterfly has the same symmetry as the sea slug, it would seem as though it matches well with it. As the question states that most organisms relate more because of symmetry, this would be a definite answer. Even though they are not the same organism family.
-Mabel <3
what properties do elements found in groups 1B–8B on the periodic table display?
Final answer:
Transition metals in groups 1B-8B on the periodic table display similar properties such as high melting and boiling points, good electrical and heat conductivity, and the ability to form colored compounds.
Explanation:
The elements in groups 1B-8B on the periodic table, also known as transition metals, display similar properties. These elements have partially filled d orbitals in their electron configurations, which give them their unique characteristics. Some common properties of transition metals include high melting and boiling points, good conductors of electricity and heat, ability to form colored compounds, and variable oxidation states.
Therefore, the required properties are high melting and boiling points, good electrical and heat conductivity, and the ability to form colored compounds.
Convert this number to its standard form 4.05x10
The answer is 40.5.
Standard form is in answered or not in a different form.
So, you must solve this.
4.05 * 10 = 40.5
Have a great day :) Let me know if you need help with anything else!
The question asked about converting a number in scientific notation to standard form. The number 4.05 x 10 is converted into its standard form by moving the decimal point of 4.05 one place to the right, which gives us 40.5.
Explanation:The number provided is in a format known as scientific notation. To convert it to its standard form, we just need to follow a few steps. The number provided is 4.05 x 10. Converting this to standard form involves multiplying the number outside the 'x' (i.e., 4.05) by 10. However, as there's no specified power of 10 provided (like 10^2, 10^3 etc.), we assume it to be 10^1. So, we simply move the decimal point in 4.05 one place to the right because it's 10^1. Thus, the standard form of 4.05 x 10 is 40.5.
Learn more about Converting Scientific Notation to Standard Form here:https://brainly.com/question/15331767
#SPJ3
Explain why the density of a metal object decreases when the object expands
The element chlorine (Cl) has two isotopes: chlorine-35 and chlorine-37. 75.5% of chlorine atoms have 18 neutrons and 17 protons, and the other 24.5% have 20neutrons and 17protons. Using the isotopic composition provided, calculate the average atomic mass of chlorine.
Answer:
35.8 u
Explanation:
The atomic mass of Cl is the weighted average of the atomic masses of its isotopes.
We multiply the atomic mass of each isotope by a number representing its relative importance (i.e., its percent abundance).
Atomic mass of Cl-35 = 17p + 18n = 17 × 1.007 u + 18 × 1.009 u
= 17.119 u + 18.162 u = 35.28 u
Atomic mass of Cl-37 = 17p + 20n = 17 × 1.007 u + 20 × 1.009 u
= 17.119 u + 20.180 u = 37.30 u
Set up a table for easy calculation.
0.755 × 35.28 u = 26.64 u
0.245 × 37.30 u = 9.138 u
TOTAL = 35.8 u
Note: The actual atomic mass of Cl is 35.45 u.
The calculated value above is incorrect because
(a) the given isotopic percentages are incorrect and
(b) the protons and neutrons have less mass when they are in the nucleus than when they are free. Thus, the calculated masses of Cl-35 and Cl-37 are too high.
The average atomic mass of chlorine can be calculated as a weighted average of its two isotopes' masses, with weights reflecting their proportions. Isotopes are variations of an element with different numbers of neutrons, and understanding them helps us calculate average atomic masses. Similar calculations apply for other elements with multiple isotopes, such as boron.
Explanation:The subject of this question is the average atomic mass of the element chlorine (Cl), given the proportions of its two isotopes: chlorine-35 and chlorine-37, with the respective proportions of 75.5% and 24.5%. The calculation is similar to finding a weighted average. This involves multiplying each individual isotope mass by its percentage (expressed as a decimal), and then adding the products together: (35amu*0.755) + (37amu*0.245).
Isotopes are variations of an element that have the same number of protons, but different numbers of neutrons. This concept is important in understanding the calculation of an element's average atomic mass. The atomic mass listed on the periodic table for each element is a weighted average of its isotopes' masses, with the weights being the natural abundance of each isotope. This is why elements, even those with atomic masses in square brackets due to their unstable nature, have precise average atomic masses.
For example, a similar element, boron, has two isotopes as well: 19.9% of all boron atoms are ¹0B with a mass of 10.0129 amu, and the remaining 80.1% are ¹¹B with a mass of 11.0093 amu. The average atomic mass for boron is then also a weighted average, calculated in a similar way to chlorine.
Learn more about Average Atomic Mass here:https://brainly.com/question/13753702
#SPJ3
how many atoms are in 80.2 grams of Calcium?
Answer:
There are [tex]1.207\times 10^{24} atoms[/tex] in 80.2 grams of calcium.
Explanation:
Atomic mass of calcium = 40 g/mol
Mass of calcium given = 80.2 g
Moles of calcium = [tex]\frac{80.2 g}{40 g/mol}=2.005 mol[/tex]
1 mol = [tex]N_A=6.022\times 10^{23} [/tex] atoms/ molecules, ions
Number of atoms of calcium in 2.005 moles of calcium:
[tex]2.005 \times 6.022\times 10^{23}=1.207\times 10^{24} atoms[/tex]
There are [tex]1.207\times 10^{24} atoms[/tex] in 80.2 grams of calcium.
The number of atoms in 80.2grams of calcium is 1.207 × 10²⁴ atoms.
How to calculate number of atoms?The number of atoms of an element can be calculated by multiplying the number of moles of the substance by Avogadro's number as follows:
no of atoms = no of moles × Avogadro's number
According to this question, 80.2grams of calcium are given. Calcium has a molar mass of 40.0g/mol. The number of moles can be calculated as follows:
no of moles = 80.2g ÷ 40g/mol = 2.005mol
No of atoms = 2.005mol × 6.02 × 10²³
no of atoms = 1.207 × 10²⁴ atoms
Learn more about atoms at: https://brainly.com/question/1566330
#SPJ4
What is an environmental impact study
An Environmental Impact Study is used to provide a sufficient level of detail to demonstrate that a proposed development will have no negative impacts on the natural features or ecological functions of the subject and surrounding (“adjacent”) lands. Hope this helps!!!
A wave travels 12 m east in 3.0 s. What is the velocity of the wave?
Answer: + 4 m/s
Working Out:
V = Δ x ÷ Δ t ;where V = velocity, Δ x = displacement, Δ t = change in time
V = Δ x ÷ Δ t
V = (12 m east) ÷ 3.0 s
V = 4 m/s to the east OR V = + 4 m/s
∴ The velocity of the wave is + 4 m/s
Answer:
4 m/s
Explanation: TOOK THE TEST
Consider the balanced reaction below:
4Al+302=2Al203
How many grams of oxygen is needed to completely react with 9.30 moles of aluminum?
[ ] g O2
The mass needed is [223] g O₂.
M_r: 26.98 32.00
4Al + 3O₂ ⟶ 2Al₂O₃
n/mol: 9.30
Moles of O₂ = 9.30 mol Al × (3 mol O₂/4 mol Al) = 6.975 mol O₂
Mass of O₂= 6.975 mol O₂× (32.00 g O₂/1 mol O₂) = 223 g O₂
drug designers are made up of scientists and
Answer:
The correct answer is chemical engineers.
Explanation:
The rational drug design also known as drug design refers to the innovative procedure of discovering novel medicines on the basis of the information of a biological target. The drug is generally a small organic constituent, which prevents or stimulates the activity of a biomolecule like a protein that in turn benefits the patient therapeutically. The drug is designed with the help of teams comprising scientists and several chemical engineers.
An aerosol can of compressed air has the following warning label: “Warning: contents under pressure. Do not expose can to heat or flame. Do not crouch can. “Using what you know about volume, pressure and temperature, explain this warning
Which compound had the highest melting point
usually its rubber please give me the brainliest!
It is yet unknown compound having highest melting point of all compounds.
It is made up of right amounts of hafnium, nitrogen, and carbon would have a melting point of more than 4400 K (7460°F).
That's about two-thirds the temperature at the surface of the sun and 200 K higher than the highest melting point ever recorded experimentally.
When scientists are ready to publish the results of their experimentation, why is it important for them to include a description of the procedures they used?
Scientists must describe their procedures and honestly report their ... should be similar- if the results are not similar and consistent then the experiment must be done again.
It is important to share the exact procedure of a science experiment, so that independent labs can repeat the experiment and arrive at similar result or observation. This helps to establish consensus in the scientific community where scientists mutually agree on a theory. Hiding any significant part from the materials and procedure section does not allow independent labs to successfully replicate the experiment.
PLEASE HALP ASAP!!!!!
1) Which of these is a chemical property of a substance?
1-reactivity
2-color
3-boiling point
4-melting point
2) Which of these is true of a chemical reaction?
1-Energy is always transferred from reactants to products.
2-Energy is always transferred from reactants to reactants
3-Energy is transferred between products and reactants.
4-Energy is not transfered.
3) Which of these is an example of physical change?
1-melting a substance
2-breaking chemical bonds
3-forming chemical bonds
4-nuclear decay
4) Which of these is an example of a chemical change?
1-cutting bread
2-spreading peanut butter
3-digesting a sandwich
4-stirring jelly
5) Which of these is an example of a physical change?
1-gasoline burning
2-metal denting
3-iron rusting
4-silver tarnishing
Reactivity is a chemical property, energy transferring between products and reactants is true of a chemical reaction, melting a substance and metal denting are physical changes, while digesting a sandwich is a chemical change.
Explanation:The chemical property of a substance from the given options is reactivity. A chemical property is related to how a substance interacts with other substances, and reactivity is an example of this.
For a chemical reaction, it's accurate to say that energy is transferred between products and reactants. During a chemical reaction, energy can either be absorbed or released, indicating a transfer of energy.
An example of a physical change from your list would be melting a substance. Physical changes involve a change in the physical properties of a substance, like its state of matter, but the substance itself doesn't change.
A chemical change involves a substance changing into a new substance with different properties. In this case, digesting a sandwich is a chemical change because it causes the food to break down into different substances.
Finally, from your list, an example of a physical change would again be metal denting. A physical change alters a substance without changing its composition, like denting a metal object does.
Learn more about Chemical and Physical Changes here:https://brainly.com/question/38109671
#SPJ3
Which statement is true about sodium hydroxide (NaOH)? It is a salt because it increases the concentration of metallic ions. It is a salt because it is formed by the reaction of an acid and a base. It is a base because it increases the concentration of hydronium ions. It is a base because it increases the concentration of hydroxide ions.
Answer:
The answer is D.) It is a base because it increases the concentration of hydroxide ions.
Explanation:
Learn more at: https://brainly.com/question/11749651
Answer:
It is a base because it increases the concentration of hydroxide ions.
Explanation: