Answer:
A. Metalloids.
Explanation:
Metalloids. Metalloids, also called semiconductors, are the elements that border the zigzag line on the periodic table.
how does a diaphragm help in viewing the specimen in a microscope
Answer:
Diaphragm controls the amount of light reaching the specimen. It is located above the condenser and below the stage. Most high quality microscopes include an Abbe condenser with an iris diaphragm. Combined, they control both the focus and quantity of light applied to the specimen.
A car takes 4 hours to cover a distance, if it travels a speed of 40 mph. What should be it's speed to cover the same distance in 1.5 hours?
Two moles of MgsO4•7H2O contain ___ grams of MgSO4•7H2O
Answer:
492.6g
Explanation:
Given parameters:
Number of moles of MgSO₄.7H₂O = 2moles
Unknown:
Mass = ?
Solution:
To find the mass of this compound;
Mass = number of moles x molar mass
Molar mass of MgSO₄.7H₂O = 24.3 + 32 + 4(16) + 7[2(1) + 16]
= 246.3g/mol
Mass = 2 x 246.3 = 492.6g
How many grams of K2Cr2O7, are soluble in 100 g of
water at 95 °C?
Answer:
75 grams
Explanation:
At 95 °C, you can dissolve up to 75 grams of K2Cr2O7 in 100 mL of water.
What is solubility?The solubility of a substance in a particular solvent is the maximum amount of that substance that can dissolve in the solvent at a given temperature. The solubility of a substance can be affected by factors such as temperature, pressure, and the presence of other substances.
For K2Cr2O7, the solubility in water is highly dependent on temperature. At 95 °C, the solubility of K2Cr2O7 in water is approximately 75 g/100 mL. This means that at 95 °C, you can dissolve up to 75 grams of K2Cr2O7 in 100 mL of water. Since 100 g of water is equivalent to 100 mL, you can dissolve up to 75 grams of K2Cr2O7 in 100 g of water at 95 °C.
Learn more about solubility, here:
https://brainly.com/question/28170449
#SPJ2
What are redox half-reactions?
Answer:
C. Equations that separate the oxidation and reduction parts of the reaction.
Explanation:
Redox half-reactions are actually used when balancing redox reactions. It gives the oxidation or reduction reaction components/parts of a redox reaction. The change in oxidation and reduction states in the substances that are involved in a redox reaction is used to obtain a redox half-reaction.
This redox half-reaction can also be used to explain what takes place in an electrochemical cell; how the anode is undergoing oxidation and how the cathode is undergoing reduction.
Below is an example of a redox half-reaction:
2 Fe³⁺(aq) + 6e⁻ → 2 Fe(s) (Reduction)
3 Mg(s) → 3 Mg²⁺(aq) + 6e⁻ (Oxidation)
White gold is used in jewelry and contains two elements, gold and palladium. A jeweler has two different samples that are both identical in appearance and have a uniform composition throughout. What can be said about the samples?
A jeweler has two different samples that are both identical in appearance and have a uniform composition throughout. (1) Since it is given that the white gold is having a uniform composition throughout.So,it means this is a Homogeneous mixtures.
a sample of carbon dioxide gas at a pressure of 1.10 atm and a temperature of 20.6 occupies a volume of 19.2 L. If the gas is allowed to expand at constant temperature to a volume of 24.3 L, the pressure of the gas sample will be ________ atm
Answer:
0.87atm
Explanation:
Given parameters:
Pressure of the gas = 1.1atm
Initial temperature = 20.6°C = 20.6 + 273 = 293.6K
Initial volume = 19.2L
New volume = 24.3L
Unknown:
New pressure = ?
Solution:
To solve this problem, we apply the Boyle's law equation:
P1V1 = P2V2
P and V are pressure and volume
1 and 2 are the initial and new states
1.1 x 19.2 = P2 x 24.3
P2 = 0.87atm
A closed container is the best way to measure the volume of a
A. gas
B. liquid
C. solid
D. Both A and B are correct.
Answer:
A closed container is the best way to measure the volume of a liquid
Can SOMEONE PLEASE HELO
Answer:
D
Explanation:
you should repeat an experiment at least 3 times
what is the empirical formula for 27.3% and 72.7% oxygen?
Answer:
27.3% of Carbon (C), 72.7% of Oxygen (O).
Give a real-world example of an energy transformation that uses two of the following forms of energy: chemical, mechanical, nuclear, gravitational, radiant, electrical, thermal (heat), and/or sound.
Answer:
Chemical Energy is energy stored in the bonds of atoms and molecules. Batteries, biomass, petroleum, natural gas, and coal are examples of stored chemical energy. Chemical energy is converted to thermal energy when we burn wood in a fireplace or burn gasoline in a car's engine.
MARK BRAINLIST PLZ NEEDS ONE MORE
Explanation:
a. Among nonpolar liquids, those with higher molar masses tend to have normal boiling points that are (higher, lower, or about the same).
b. Among compounds of approximately the same molar mass, those with greater polarities tend to have enthalpies of vaporization that are (higher, lower, or about the same).
c. Which is the only noble gas listed that is stable as a liquid at 0°C? Explain your answer using the concept of critical temperature.
Answers are below...and I have answered this question on the basis of above table.
Explanation :-
(a.) Among nonpolar liquids, those with higher molar masses tend to have normal boiling points that are (lower).
(b.) Among compounds of approximately the same molar mass, those with greater polarities tend to have enthalpies of vaporization that are (higher).
(c.) Xe (Xenon), a substance can exist only as a gas at temperatures above its critical temperature. Of the noble gases listed, only Xe has a critical temperature above O°c.
Among nonpolar liquids, those with higher molar masses tend to have normal boiling points that are lower. Among compounds of approximately the same molar mass, those with greater polarities tend to have enthalpies of vaporization that are higher.Xenon can exist only as a gas at temperatures above its critical temperature.
What is a compound?Compound is defined as a chemical substance made up of identical molecules containing atoms from more than one type of chemical element.
Molecule consisting atoms of only one element is not called compound.It is transformed into new substances during chemical reactions. There are four major types of compounds depending on chemical bonding present in them.They are:
1)Molecular compounds where in atoms are joined by covalent bonds.
2) ionic compounds where atoms are joined by ionic bond.
3)Inter-metallic compounds where atoms are held by metallic bonds
4) co-ordination complexes where atoms are held by co-ordinate bonds.
They have a unique chemical structure held together by chemical bonds Compounds have different properties as those of elements because when a compound is formed the properties of the substance are totally altered.
Learn more about compounds,here:
https://brainly.com/question/13516179
#SPJ2
Which of the following is not a property of most
transition metals?
Answer:
Low melting point
Explanation:
Transition metals have the following properties:
Conductivity (Electrical and Thermal)
Malleability (You can hit it with a hammer to mold it)
High melting point
Answer:
Low melting point
Explanation:
Most transition metals property is high melting point.
How do particles Behave differently in a solid, liquid, or gas
Answer:
gas vibrate and move freely at high speeds. liquid vibrate, move about, and slide past each other. solid vibrate (jiggle) but generally do not move from place to place.
Answer:
The soilds vibrate in a fixed position and are very packed together whilst in liquids they are close together but they can move around and gases are widely spaced and move around randomly
Explanation:
30g of solute is dissolved in 100g of water. Calculate its % (m/m) concentration.
Answer:
23%
Explanation:
First to help me with these 4 gets brainless HURRYTTT UPPPPP
Answer: It's A
Explanation:
Answer:
A
Explanation:
What is one possible excited state configuration for fluorine? *
Answer:
Excited State Configuration: 1s^2 2s^2 2p^4 3s^1 are sperated by 13.00 eV.
Which of these best describes a scientific law?
• a rule made by a government
• a rule that does not depend on observable evidence
• a statement which varies under the same conditions
• a statement about how things act in the natural world
Helpppppppp I honestly have no clue
How many moles are in 54 grams of C?
Chemistry, Good amount of points for help!!
Answer:
Where are all my chemistry geniuses at?
1. The pattern of electronegativities would increase as you go across a period and would decrease as you go down a group in the periodic table.
2. There is a correlation between electronegativity and atomic radius. As electronegativity increases, atomic radius decreases. As electronegativity decreases, atomic radius increases. This would make sense because as a atomic radius increases, them more farther away the electrons are away from the nucleus because of their many subshells making it less electronegative. As atomic radius decreases, the electrons are more closer to the nucleus because of their few subshells making the element more electronegative.
3. There is a correlation between ionization energy and electronegativity. As electronegativity increases, ionization energy increases as well. If it decreases, ionization energy decreases too. This makes sense because the more electronegativity the element, the more they are closer to the nucleus(making them harder to remove) and the more desperate for an electron the atom is.
Explanation:
Hope it helped!
What is the mass in grams of 0.40 moles of sodium borohydrate NaBH4
Answer:
Mass = 15.12 g
Explanation:
Given data:
Mass of sodium borohydride = ?
Number of moles of sodium borohydride =0.40 mol
Solution:
Formula:
Mass = number of moles / molar mass
Molar mass of sodium borohydride = 37.8 g/mol
By putting values,
Mass = 0.40 mol × 37.8 g/mol
Mass = 15.12 g
Consider the reaction below.
2 Na + O2 → Na2O2
If 10.0 g of sodium metal reacts with excess oxygen gas how many grams of sodium oxide will be produced?
Show your work below. Make sure to show ALL units and each step of the process:
Answer:
I think 5
Explanation:
An atom of barium has the atomic symbol shown below. Which statement is FALSE regarding this atom of barium?
Answer:
C. The atomic number of this atom is 138
Explanation:
Answer:
C
Explanation:
The Atomic mass if hydrogen us 1.008 amu. The reason that this value is not a whole number is that
A. The Mass of hydrogen is the sum of the masses of the protons and electrons in the atom
B. Hydrogen has more than one isotope
C. Hydrogen only exists as a diatomic molecule
D. The Mass of a proton is not exactly equal to 1 amu
Answer:
I'm pretty sure its c
Explanation:
The atomic mass of hydrogen, which is 1.008 amu, is not a whole number because hydrogen has more than one isotope.
The atomic mass of an element is got from the sum of the proton and neutron in its atom. However, the atoms of some element exists in more than one isotope. Isotopes are atoms of the same element with same atomic number but different atomic masses. The different atomic masses arise from the difference in the number of neutrons of each isotope. Hydrogen has more than one isotope. The atomic mass of an element with more than one isotope is the weighted average of the mass numbers of the different isotopes of that element, hence, the resulting value cannot be a whole number.Learn more at: https://brainly.com/question/11680817?referrer=searchResults
can we seperate naphthalene from sugar by filtration to obtain pure sugar?
Answer:
As Naphthalene undergoes sublimation, we use sublimation process. On condensing naphthalene can be separated.
If 15.7 grams of A1203 are produced, how many grams of iron (Fe) were
produced?
2 Al(s) + 3 FeO(s) → 3 Fe(s) + Al2O3(
The children in the class are more than 10 years old
Answer:
The children have spent 5 of there years playing and having the time of there lives and the other 5 years are spent losing and gaining brain sells!
hope this helps:)
so sorry if this is wrong!
Which most likely represents the process of dissolving carbon dioxide in soda?
increased temperature to increase solubility
increased pressure to increase solubility
decreased agitation to decrease solubility
decreased pressure to increase solubility
Answer:
its increased pressure to increase solubility
Answer:
B
Explanation:
i took the quiz
What causes the wind and weather on earth plz help