Which of the following statements describes the elements within a row of the periodic table?
A. They are in the same family.
B. They have the same or nearly the same properties.
C. They have the same average atomic mass.
D. They have properties that change in a pattern.
Why does everyone keep saying I should call Uraraka “red cheeks” instead of “pink cheeks” (=_=)
i dont know man they're weird
What is a unwanted change in the environment caused by substances or from of energy??
Answer:
pollution I think
Explanation:
23. Under which conditions would carbon dioxide be most soluble in water?
O 1) 10°C and 1 atm
O2) 10°C and 2 atm
3) 20°C and 1 atm
4) 20°C and 2 atm
Answer:
20°C and 2 atm is correct
Explanation:
What do you think is the primary reason why the Unionid mussel population declined whenever there is a dramatic increase in the Zebra mussel
Answer:
When the Zebra arrived they ate all the food so the Unionid mussels declined as they died from the lack of food. Causing the Zebra Zebra numbers to increase and Unionid numbers to decline.
Need help fast plzzz!!! Please help.
Answer:
1. 0.5333333m (Calculator Soup Work Calculator)
2.
9. 29.1666666667% efficient
10. 44.5% efficient
Explanation:
will do other answers later
Which describes the substances that form covalent bonds?
A. a metal and a metalloid
B. a metal and a nonmetal
C. two nonmetals
D. two metals
PLS HELPPPP ME!!!!
What term do we use when the moon's light is going away and the moon seems
to be "shrinking" each day? Hint: Karate Kid: "Wax on wane off.”
HELPP PLSSSSS
To slow down the flow of electrons in a circuit is called
Answer: Resistance slows down the flow of charge in a circuit. The unit of resistance is the ohm (Ω) which is defined as a volt per ampere of current.
Explanation:
Vectors are arrows that tell us two things about force...WEIGHT and DIRECTION
True
False
True or False vacuoles direct cell activities by sending instructions to different parts of an animal cell
Answer:
False
Explanation:
The nucleus controls the cells activities
4.3 moles of a gas are at a temperature of 28 degrees * C with a pressure of 1.631 atm. What volume does the gas occupy?
Answer:
65.2L
Explanation:
Using the general gas equation;
PV = nRT
Where;
P = pressure (atm)
V = volume (Litres)
n = number of moles (mol)
R = gas law constant (0.0821 Latm/molK)
T = temperature (Kelvin)
According to the information provided in this question,
P = 1.631 atm
V = ?
n = 4.3 moles
T = 28°C = 28 + 273 = 301K
Using PV = nRT
V = nRT/P
V = 4.3 × 0.0821 × 301 ÷ 1.631
V = 106.26 ÷ 1.631
V = 65.15
Volume of the gas = 65.2L
Calculate the ratio of H+ ions to OH– ions at a pH = 6. Find the concentration of H+ ions to OH– ions listed in Table B of your Student Guide. Then divide the H+ concentration by the OH– concentration. Record this calculated ratio in Table A of your Student Guide. Compare your approximated and calculated ratios of H+ ions to OH– ions at a pH = 6. Are they the same? Why or why not? Record your explanation in Table A. What is the concentration of H+ ions at a pH = 6? mol/L What is the concentration of OH– ions at a pH = 6? mol/L What is the ratio of H+ ions to OH– ions at a pH = 6?
Answer:
Answer:
You must know the concept of pH of a solution and its relation to the concentration of H+ and OH- ions. pH is a measure of the substance's acidity or basicity. From the definition of Arrhenius, an acid contains an H+ while a base contains a OH- ion. From this definition, we can say that an acidic substance has a higher concentration of H+ ions. Now, I'll introduce here that pH is the value of the negative logarithm of the concentration of H+. In equation,
pH = -log[H+]
The term pOH is therefore also, pOH = -log[OH-]. Therefore, the relationship that connects the two negative logarithms is:
pH + pOH = 14
The pH scale starts from 1 being the most acidic to 14 being the most basic. The neutral pH is 7. Thus, for a pH of 7, the H+ and the OH- concentrations are equal.
pH = 7 = -log[H+]
[H+] = 1×10⁻⁷ mol/L = [OH-]
Since the concentrations are equal, the ratio is equal to 1.
how many moles of Si are in 78.0 grams of silicon
Answer:
[tex]\boxed {\boxed {\sf 2.78 \ mol \ Si}}}[/tex]
Explanation:
To convert from grams to moles, we must use the molar mass. This number can be found on the Periodic Table.
Si (Silicon): 28.085 g/molWe can use number as a ratio.
[tex]\frac { 28.085 \ g \ Si}{ 1 \ mol \ Si}[/tex]
Multiply by the given number of grams.
[tex]78.0 \ g \ Si *\frac { 28.085 \ g \ Si}{ 1 \ mol \ Si}[/tex]
Flip the fraction so the grams of silicon cancel.
[tex]78.0 \ g \ Si *\frac {1 \ mol \ Si }{ 28.085 \ g \ Si}[/tex]
[tex]78.0 *\frac {1 \ mol \ Si }{ 28.085 }[/tex]
[tex]\frac {78.0 \ mol \ Si }{ 28.085 }= 2.77728324729 \ mol \ Si[/tex]
The original number of grams (78.0) has 3 significant figures, so our answer must have the same. For the number of moles calculated, that is the hundredth place. The 7 in the thousandth place tells us to round the 7 to a 8.
[tex]2.78 \ mol \ Si[/tex]
There are about 2.78 moles of silicon in 78.0 grams.
Can you please help me !!
Answer:
Explanation:
A) O2 (non polar covalent)
B) HF (polar covalent)
C) NaCl (because its ionic)
im not 100% sure hope it helps
What is a endothermic reaction
Answer:
Basically, it's heat transfer!
Good luck!Answer:
An endothermic process is any process with an increase in the enthalpy H of the system. In such a process, a closed system usually absorbs thermal energy from its surroundings, which is heat transfer into the system.
Explanation:
huryyyyyy plsssssssssssssssssss
Answer:
B.
Explanation:
bc it goes from having the potential to move to moving sorry if im wrong tho
What is the volume of 55 grams of carbon dioxide at STP
A. 2.45 L
B. 28 L
C. 1.25 L
D. 12.5L
Answer:
A. 2.45 L - Answer my answers is right.
If a nitrogen atom has 7 protons and 7 neutrons, what is its mass?
A book that slides off a desk will fall to the floor. What is it the moves the book and all other objects, downward?
Group of answer choices
Friction with other objects
Air pressure pushing from above
The force of gravity
Earth's magnetic fields
Answer:
Answer down below!
Explanation:
It would be the force of gravity, because gravity pulls all things toward the center of the Earth. If the book would have fallen down, the force of gravity was put in place.
Answer: The force of gravity
Explanation:
gravity is a force the brings thins towards the core, aka the ground
Calculate the mass of potassium in 500g of potassium sulfate?
Answer:
174.94
Explanation:
Which of these can be used as an inert electrode?
copper
platinum
silver
zinc
Answer:
I believe it is platinum
Explanation:
I think it is, haha
Answer:
zinc
Explanation:
kwkejnrkewnrkwe
Do you think this one experiment is enough to change the scientific theory regarding the speed of light?
No. The speed of light does change. You mean speed of light in a vacuum. Measuring that value is elementary, in a 2-way measurement, as you show.
What is a primary difference between bacteria that are
in the kingdom Archaea and other bacteria?
Answer:Both atractive and repulsie
Explanation:
Write the number 0.0000087 in scientific notation.
Answer:
8.7 × 10-6
Explanation:
sorry if incorrect
Answer:
[tex]8.7 \times {10}^{ - 6} [/tex]
Explanation:
[tex]0.0000087[/tex]
[tex]8.7 \times {10}^{ - 6} [/tex]
Isotopes are atoms of the same element that have different O principal chemical properties, masses. O numbers of protons, O numbers of electrons.
Answer:
Different atomic mass, number of neutrons
Explanation:
Isotopes refer to atoms of the same element, with same atomic number, number of protons & electrons. However, they have different atomic mass, because of different number of neutrons.
What are the characteristics of the three states of matter?
Solid:
Liquid:
Gas:
In your own words, describe the process of convection.
Answer:
the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat
Explanation:
<3
Answer:
Convection when heat travels through metal or appliances.
Explanation:
Compared to Earth, Mercury rotates on its axis very slowly. Based on this information, what can you conclude about Mercury?
O Mercury applies weaker gravitational forces on objects.
O The length of a day on Mercury is much longer than Earth.
O Mercury has no atmosphere.
O The surface of Mercury is rocky.
PI
Hidderi
Answer:
2nd down
Explanation:
''The length of a day on Mercury is much longer than Earth'' is the right answer.
Daylength on Mercury as compared to earthMercury rotates on its axis very slowly due to which daylength on Mercury is much longer than Earth. A day on Mercury is 1407.5 hours long while a day on Earth is 23.934 hours long and its reason is slower rotation of Mercury so we can conclude that ''The length of a day on Mercury is much longer than Earth'' is the correct option.
Learn more about Mercury here: https://brainly.com/question/879
what is 15 /2.343*233+2341
if you are reading this you like the person you are sitting beside or just beside or will sit beside next.
Answer:
3832.67
Explanation: