Answer:
the farther they are the longer there cycle is. closer they are shorter time.
Which of these elements is the most chemically reactive?
A.
strontium (Sr)
B.
beryllium (Be)
C.
radium (Ra)
D.
calcium (Ca)
The most chemically reactive element among the listed elements is Radium (Ra). The correct option is C. radium (Ra)
The elements listed are alkaline earth metals, that is, they belong to group 2 of the period table.
The reactivity of alkaline earth metals increases down the group. That is, the reactivity increases with increase in atomic mass.
Among the listed element, radium (Ra) has the greatest atomic mass and it is the last element as we go down the group.
Hence, the most chemically reactive element among the listed elements is Radium (Ra). The correct option is C. radium (Ra)
Learn more here: https://brainly.com/question/3288105
Among the groups of elements listed below, which have the same number of electrons in their outermost energy levels? C, K, Ca, Rb, Sr
Na,Mg,AI,S
Li,B,C,F
F,CI,Br,I
Answer:
i believe its d
Explanation:
Answer:
I checked and I too think its D
2Mg + O2
2Mgo
what is the coefficient
Answer:
In this chemical equation, there are two main elements. Those elements are magnesium (Mg) and oxygen (O). Molecules are a group of atoms bonded together, and in this case, the oxygen molecules is O2, but not 2MgO because there are two different molecules in this compound. Coefficients are a number that multiply an entire molecule, and are also placed in front of it. In this case, O2 has no coefficient, but a subscript of 2. But, every molecule in this equation must have a coefficient and if add a coefficient of 1 to the oxygen molecule, it does nothing to the overall balancing of equations.
So, the answer: coefficient to the oxygen molecule is 2.
Have a great day/night, stay safe, and merry christmas!
WILL GIVE BRAINLIEST
Which statement describes earthquakes?
They release energy.
They are caused by reduced stress in rocks.
They begin at the epicenter.
They result from movement on Earth’s surface.
Answer:
A
Explanation:
A 10.-liter flask at a given temperature and pressure contains 6.0 × 1023 molecules of hydrogen gas. Under the same conditions of temperature and pressure, how many molecules would a 10.-liter flask of nitrogen gas contain?
Answer:
The same number of molecules, 6.0 × 10²³ molecules.
Explanation:
The amount of any given gas that can be stored in a container depends on the temperature, pressure and volume of the container. It does not depend on the nature (or identity) of the gas.
So if a 10-liter flask contains 6.0 × 10²³ molecules of hydrogen gas, it will contain the same amount of molecules of any other gas when temperature and pressure remain constant.
What is this plzzzzz helppp tyvmmmm
ANSWER THESE 5 MULTPLE CHOICE QUESTIONS!!!
I'LL GIVE 30 POINTS AND A BRAINIEST:)
Answer: 1, magnesium & mg
2, two energy shells
Explanation:
Object A has a mass of 500g and object B has a mass of 300g. Which object is more dense?
Answer:
500g because 300g is less dense than 500g its kinda like a weight
Explanation:
i
Question 6 W If 50. mL of 1.0 M NaOH is diluted with distilled water to a volume of 2.0 L, the concentration of the resulting solution is А 0.025 M B 0.050 M C 0.10 M D 0.50 M E 1.0 M
Answer:
im not sure man
Explanation:
Which would balance the equation? (Look at picture on my laptop)
-3
-4
-1
-2
The answer is 2
2H2 + O2 ---> 2H2O
Highlight the larger unit of measure under each letter (a-f). Then, write if the unit highlighted measures distance, volume, or weight (mass).
a. meter or kilometer
b. yard or foot
c. cup or quart
d. pound or ounce
e. liter or milliliter
f. gram or kilogram
Answer:
2. The unit could be gram or kilogram ⇒ answer f
3. The larger unit is kilogram and measures weight (mass)
Step-by-step explanation:
Let us revise the SI units of measuring
The SI unit of measuring distance is meter
The SI unit of measuring volume is liter
The SI unit of measuring mass is kilogram
2.
When this pet hamster is placed on a digital scale, the scale reads 1.5
∵ The SI unit of measuring weight (mass) is kilogram
∵ The scale reads 1.5
∴ The unit is kilogram
The unit could be gram or kilogram
3.
∵ The larger unit of measure is kilogram
∵ Kilogram measures the weight (mass)
∴ The unit measures weight (mass)
The larger unit is kilogram and measures weight (mass)
Explanation:
1. The molecular mass of hydrochloric acid (HCI) is 36.5 g/mol. How many moles of HCl are in 120g of HCI?
Answer:
3.3 mol HCl
General Formulas and Concepts:
Chemistry - Atomic Structure
Using Dimensional AnalysisExplanation:
Step 1: Define
120 g HCl
Step 2: Identify Conversions
Molar Mass of HCl - 36.5 g/mol
Step 3: Convert
[tex]120 \ g \ HCl(\frac{1 \ mol \ HCl}{36.5 \ g \ HCl} )[/tex] = 3.28767 mol HCl
Step 4: Check
We are given 2 sig figs as our lowest. Follow sig fig rules and round.
3.28767 mol HCl ≈ 3.3 mol HCl
The purpose of warfare in our world
Answer
We are currently working on a dataset of war and large-scale violent events over the long run. If you want to contribute to this research please get in touch.
Explanation:
Hydrofluoric acid is what type of acid?
Hydrofluoric acid is a solution of hydrogen fluoride (HF) in water. Solutions of HF are colourless, acidic and highly corrosive. It is used to make most fluorine-containing compounds; examples include the commonly used pharmaceutical antidepressant medication fluoxetine (Prozac) and the material PTFE (Teflon).
any help would be much appreciated, i'm being timed :( i'll mark brainliest and 5 star
Answer:
3 times ....
group 2
Explanation:
this graphs represents
The mode of 12, 17, 16, 14, 13, 16, 11, 14,13, 16 is
Answer:
Mean = 14.2Median = 14Mode = 16Range = 6Explanation:
__________________________________________________________
Mean = 14.2 or 14
Median = 14
Mode = 16
Range = 6
__________________________________________________________
Here are all the numbers from least to greatest order: 11, 12, 13, 13, 14, 14, 16, 16, 16, 17.
__________________________________________________________
Hope this helps! <3
__________________________________________________________
Se sabe que un compuesto contiene 33.002% de carbono,9.063% de hidrogeno y el resto de oxigeno. El espectrometro de masas indica que la masa molecular aproximada es de 191g/mol(cual es la formula empirica y molecular probable
Answer:
CH3O
C6H18O6
Explanation:
Porcentaje de masa de oxígeno = 100% - (33,002% + 9,063%) = 57,935%
Divida el porcentaje en masa de cada elemento por su masa atómica relativa;
H- 9.063 / 1, C- 33.002 / 12, O - 57.935 / 16
H- 9.063, C- 2.75, O- 3.62
Dividir por la proporción más baja;
H-9.063 / 2.75, C- 2.75 / 2.75, O- 3.62 / 2.75
H- 3, C-1, O- 1
Fórmula emperical = CH3O
Dado que la masa molecular es 191 g / mol
Sea n el número de cada átomo de la molécula
Por tanto, su fórmula molecular es; (CH3O) n = 191
[12 + 3 (1) + 16] n = 191
31n = 191
n = 191/31
n = 6
Por lo tanto, la fórmula molecular del compuesto es; (CH3O) 6 que es C6H18O6
The process in which the nuclei of two atoms combine to form a heavier atom, releasing a large amount of energy is known as -
Answer: Nuclear fusion
Explanation:Nuclear fusion is the process by which two or more atomic nuclei join together to form a single heavier nucleus and large amounts of energy.
If 1520 J are added to 16.5 g of water at 63.1 c what will the final temperature be
A student drops a ball from 5 feet above the ground. After bouncing once, it only reaches a maximum height of 4 feet above the ground. Use energy terms to explain why the ball did not reach its original height after bouncing once.
Answer:
because the gravity of the ball can't go that high
There is a law called conservation of energy which states that energy can neither be created nor be destroyed. It can be only transferred from one form to another form. Therefore, some energy is lost to the environment as sound or heat.
What is energy transfer?Energy transfer is a phenomenon in which energy transfer from one matter to another matter. Energy can be transferred in two forms that are by doing work or by transferring heat.
Heat can be transferred by three ways conduction, convention and radiation. In conduction, when two object are in direct contact, transfer of molecules takes place. As the ball impacted the ground, the energy would have been lost to the environment as sound or heat.
Therefore, some energy is lost to the environment as sound or heat.
Learn more about energy transfer, here:
https://brainly.com/question/18649915
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Why is radium more reactive than calcium?
I’ll mark you brainlist
Answer:
High mass star.
Explanation:
The mass of a star defines its life span. the least massive stars will live the longest and the most massive stars will use their fuel in a few million years and end in a spectacular supernova.
How many significant digits would you report an answer to if you divided 2.654 by 3.2?
answer choices
1
2
3
4
Answer:1
Explanation:
How many Elements are in the following molecule -CHNaO
Answer:
4 elements
C carbon
H hydrogen
Na sodium
O oxygen
Explanation:
A block of material has a volume of 50 cubic centimeters, and a mass of 1,000 grams; what is that object's density?
O Why are you asking me this question??
0 .02 cc/g
O None of these answers N
O All of these answers
20 g/cc
050,000 g/cc
O 5 g/ccccc
Answer:
Density = [tex]20\ g/cm^3[/tex]
Explanation:
Given that,
Mass of the object, m = 1000 g
Volume of the block, V = 50 cm³
We need to find the density of the object. Density is equal to mass per unit volume.
d = m/V
[tex]d=\dfrac{1000\ g}{50\ cm^3}\\\\=20\ g/cm^3[/tex]
So, the density of the object is [tex]20\ g/cm^3[/tex].
how many bonds can nitrogen have
Answer:
3
Explanation:
I think so, let me know if its wrong.
What is the wavelength of electromagnetic radiation which has a frequency of 4.464 x 10^14 s-1
a. 1.338 x 10^23 m
b. 1.489 x 10^-6 m
c. 6.716 x 10^-7 nm
d. 671.6 nm
Answer:
d. 671.6 nm
Explanation:
It is possible to solve the wavelength of a radiation from its frequency -or vice versa- using:
λ = c / f
Where λ is wavelength,
c is speed of light, a constant (2.998x10⁸m/s)
And f is frequency: 4.464x10¹⁴s⁻¹
Replacing:
λ = 2.998x10⁸m/s / 4.464x10¹⁴s⁻¹
λ = 6.716x10⁻⁷m
As 1m = 1x10⁹nm:
6.716x10⁻⁷m * (1x10⁹nm / 1m) = 671.6nm
Right answer is:
d. 671.6 nm
A material that conducts electricity only at high temperatures.
A.Semiconductor
B.Compound
C.Luster
D.Brittle
Answer:
Semiconductor
Explanation:
Semiconductors conduct electricity as the temperatures increase.
Hope this helped.
Una muestra de 2,36 gramos de NaHCO3 se descompuso completamente en un experimento. 2NaHCO3 → Na2CO3 + H2CO3 En este experimento, el dióxido de carbono y los vapores de agua se combinan para formar H2CO3. Después de la descomposición, el Na2CO3 tenía una masa de 1,57 gramos. Determine la masa del H2CO3 producido. Calcule el porcentaje de rendimiento de H2CO3 para la reacción.
Answer:
105%
Explanation:
El porcentaje de rendimiento se define como la masa obtenida del producto (En este caso, en términos de H2CO3), dividida en la masa teórica que debe ser producida.
La masa real se obtiene con las moles del otro producto que fueron producidas (Que son las mismas moles producidas de H2CO3)
Y la masa teórica se obtiene a partir de las moles de reactivo adicionadas:
Masa teórica:
2.36g NaHCO3 * (1mol / 84g) = 0.0281 moles de NaHCO3
0.0281 moles de NaHCO3 * (1mol H2CO3 / 2 moles NaHCO3) =
0.014 moles de H2CO3 son producidas. La masa es:
0.014 moles de H2CO3 * (62g / mol) = 0.871g es la masa teórica
Masa real:
1.57g Na2CO3 * (1mol / 106g) = 0.014 moles de Na2CO3
0.0148 moles de Na2CO3 * (1mol H2CO3 / 1 moles Na2CO3) =
0.0148 moles de H2CO3 son producidas. La masa es:
0.0148 moles de H2CO3 * (62g / mol) = 0.918g es la masa real producida
Así, el porcentaje de rendimiento es:
0.918g / 0.871g * 100 =
105%