Answer:
Li2Se
Lithium selenide
Explanation:
A pharmacist mixed some 10%-saline solution with some 15%-saline solution obtain 100 mL of a 12%-saline solution. How much of the 10-saline solution did the pharmacist use in the mixture
Answer:
10%-saline solution = 60mL
15%-saline solution = 40mL
Explanation:
Let
10%-saline solution = x
15%-saline solution = y
x + y = 100
0.1x + 0.15y = 100*0.12
x + y = 100 (1)
0.1x + 0.15y = 12 (2)
from (1)
x = 100 - y
Substitute x = 100 - y into
0.1x + 0.15y = 12
0.1(100 - y) + 0.15y = 12
10 - 0.1y + 0.15y = 12
- 0.1y + 0.15y = 12 - 10
0.05y = 2
y = 2 / 0.05
y = 40mL
Substitute y = 40 into
x + y = 100
x + 40 = 100
x = 100 - 40
x = 60mL
10%-saline solution = 60mL
15%-saline solution = 40mL
What is the similarity between teeth and eggshells?
*. Please answer
Answer: Eggshells have a similar chemical composition to our tooth enamel, making them react similarly with other chemicals. This can help us understand what stains tooth enamel. When we brush an eggshell with fluoridated toothpaste, it strengthens the shell and protects it from acid, just like it does for our tooth enamel
Explanation:
Answer: Eggshells have a similar chemical composition to our tooth enamel, making them react similarly with other chemicals. This can help us understand what stains tooth enamel. When we brush an eggshell with fluoridated toothpaste, it strengthens the shell and protects it from acid, just like it does for our tooth enamel.
. How do metals and non-metals
Which two properties of metal enable us to use metal as electric wire
Answer:
it's ductility and it's conductivity
Explanation:
Helium (He), neon (Ne) and argon (Ar) are all colorless, odorless gases with low chemical reactivity. Based on the periodic table, which other element would also have those same properties?
Answer:
Given above are noble gases and other noble gases would be xenon, radon, oganesson, krypton.
hope it helps!
Answer: A
Explanation: just did it
3. Hydrogen reacts with nitrogen to produce ammonia according to the equation:
3H2(g) + N2(g) 2NH3(g)
Determine how much ammonia would be produced if 100g of N2 reacts?
Mass of ammonia produced : 121.38 g
Further explanationGiven
Reaction
3H₂(g) + N₂(g) ⇒ 2NH₃(g)
100g of N₂
Required
Ammonia produced
Solution
mol of N₂ :
[tex]\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{100}{28}\\\\mol=3.57[/tex]
From the equation, mol ratio of N₂ and NH₃ = 1 : 2, so mol NH₃ :
[tex]\tt \dfrac{2}{1}\times 3.57=7.14~moles[/tex]
mass of NH₃(MW=17 g/mol) :
[tex]\tt mass=mol\times MW\\\\mass=7.14\times 17\\\\mass=121.38~g[/tex]
Daniel and Sanya are scientists. Daniel is studying whether the increasing frequency of tropical storms is affecting coastal erosion. Sanya is investigating whether the discharge from industrial plants has any impact on the pH concentration of freshwater swamps in the surrounding area. Which fields of science are Daniel's and Sanya's studies most closely related to?
Daniel's field of study is related to [biological, earth and space,or physical] science, and Sanya's field of study is related to [biology, chemistry, or physics].
Answer:
- Daniel- Earth and Space
- Sanya- Chemistry
Explanation:
Daniel's study field is associated with the 'Earth and Space' as he is attempting to explore how the frequency of tropical storms(in the atmosphere) and coastal erosion(relation with land and ocean) are interconnected to each other. He studies how the two are associated and affect life on the planet.
While Sanya's field of study would be 'Chemistry' as she aims to study the composition and constitution of substances and the changes that they undergo as a consequence of alterations in the constitution of their molecules('whether the discharge from industrial plants has any impact on the pH concentration of freshwater swamps in the surrounding area').
14. HCOOH is an example of
A. alcohols.
B. aldehydes.
C. carboxylic acids.
D. ethers.
E. ketones.
Answer:
carboxylic acid is the answer
Explanation:
Plz mark brainliest
What is the charge of a beta particle?
Answer:
Beta particles have a charge of minus 1.
Explanation:
Hope this helps!
Answer:
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Explanation:
Beta particles have a mass which is half of one thousandth of the mass of a proton and carry either a single negative (electron) or positive (positron) charge. As they have a small mass and can be released with high energy, they can reach relativistic speeds (close to the speed of light)
HOPE IT HELPS YOU
Which of the following best describes the velocity of an object?
A B0 m/s
B 30 m east
C 30 m/s east
D 30 m/s2
Answer:
[tex]\boxed {\boxed {\sf C. \ 30 \ m/s \ east}}[/tex]
Explanation:
Velocity is the vector measurement of the change in position over time. A vector measurement means the answer must include a magnitude (numerical value) and a direction.
Here are some units of velocity:
m/s (meters per second) kph (kilometers per hour) km/s (kilometers per second)There are many other units, but m/s is the most common.
We can eliminate choice B and D, because the units (meters-m and meters per second squared-m/s²) are not for velocity.
We are left with choice A (30 m/s) and C (30 m/s east). Remember, velocity needs a number and a direction. C contains the direction east, so it must be the correct answer.
How many total valence electrons are found in the following molecules: CO3
Answer:
The Carbonate (CO2−3) Ion
Unlike O3, though, the actual structure of CO32− is an average of three resonance structures. 2. Carbon has 4 valence electrons, each oxygen has 6 valence electrons, and there are 2 more for the −2 charge. This gives 4 + (3 × 6) + 2 = 24 valence electrons
Explanation:
how many moles of barium hydroxide would be required to react with 117 g hydrogen bromide?
How many milliliters of sodium metal, with a density of 0.97 g/mL, would be needed to produce 34.5 grams of sodium hydroxide in the single replacement reaction below?
Unbalanced equation: Na + H2O ---> NaOH + H2
Volume of Sodium metal : 20.454 ml
Further explanationReaction(balanced) :
2Na + 2H₂O → 2NaOH + H₂
mass NaOH = 34.5 g
mol NaOH(MW=40 g/mol) :
[tex]\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{34.5}{40}\\\\mol=0.8625[/tex]
From the equation, mol ratio of Na : NaOH = 2 : 2, so mol Na=mol NaOH=0.8625
Mass Na (Ar=23 g/mol):
[tex]\tt mass=mol\times MW\\\\mass=0.8625\times 23\\\\mass=19.84~g[/tex]
Volume Na :
[tex]\tt V=\dfrac{m}{\rho}\\\\V=\dfrac{19.84~g}{0.97~g/ml}\\\\V=20.454~ml[/tex]
What is the mass of 3.25 miles of AsF5
Answer:
169.913616 g/mol
Explanation: This is weight of AsF5 molecular weight
how many protons does the neutral atom pictured have?
A) 8
B) 18
C) 2
D) 20
Answer:
b 18
Explanation:
Aluminium and oxygen react to produce aluminium oxide,
4 Al + 3 02 - 2 AL,O
How many kilograms of aluminium oxide are formed when 5,4 kg of aluminium react
with excess oxygen?
A 5,4 kg
B 88 kg
C 10.2 kg
D 33,6 kg
The balanced reaction is
4 Al + 3 O₂ → 2 Al₂O₃
so that for every 4 moles of Al and 3 moles of O2, you end up with 2 moles of Al₂O₃.
• Al has molar mass ≈ 26.982 g/mol
• O has molar mass ≈ 15.999 g/mol
• Al₂O₃ thus has molar mass ≈ 101.961 g/mol
You start with 5.4 kg = 5,400 g of Al, or
(5.4 kg Al) • (1/26.982 mol/g) ≈ 200.133 mol Al
Al₂O₃ is produced in a ratio of 2 moles to every 4 moles of Al, so you end up with about 100.067 mol Al₂O₃, which has a mass of
(100.067 mol Al₂O₃) • (101.961 g/mol) ≈ 10,202 g = 10.2 kg
so the answer is C.
Chemical Equations :p
Explanation:
4NH₃ (g) + 5O₂ (g) → 4NO (g) + 6H₂O (g) Ba(ClO₃)₂ (s) → BaCl₂ (s) + 3O₂ (g) 2Al (s) + 3Zn(NO₃)₂ (aq.) → 3Zn (s) + 2Al(NO₃)₃ (aq.) 2C₈H₁₈ (g) + 25O₂ (g) → 16CO₂ (g) + 18H₂O (g)how long does it take to drive a distance of 260 miles at a speed of 65 mph?
Answer:
4 hours
Explanation:
What is the kinetic energy of a population of particles?
Answer/Explanation:
The kinetic energy of a particle is one-half the product of the particle's mass m and the square of its speed v: K=12mv2.
Choose all that are correct about the elements in the column highlighted in blue
in the periodic table below (there are FOUR correct answers)
help !!!
Answer:
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The overall long-term effects of air pollution are not yet certain.
True
False
Answer:
its true
Explanation:
because I made sure it was true and it is
Which pair of statements most accurately describes Earth's position relative to
the sun in late March and in late September?
Answer:
A
Explanation:
Differentiate between acids and bases on the basis of their pH values.
Answer:
acid; there ph value is mostly 7
base: there ph value can be more than 7 or less than 7
Answer:
The more towards 0 a pH value is, the increasingly acidic. Conversely, the more towards 14 a pH value is, the increasingly alkaline. Some examples of bases are lye, ammonia, and seawater. Some examples of acids are vinegar, lemon juice, and battery acid. To determine the pH of a liquid, you can use pH strips. Depending on the color (the redder the more acidic, the bluer the more alkaline), you can determine the pH of whatever you are trying to measure.
3. Which of the following is an example of a polyatomic ion?
a. NO
b. OP-
C. CI
d. Ca²+
Answer:D
Explanation:polyatomic means more then one and it have more then 1 positive ion
Which are long chains formed by the process of polymerization?
1. subunits
2. ethylenes
3. monomers
4. DNA strands
Answer:
Monomers are long chains formed by the process of polymerization
Explanation:
Answer:
monomers is the correct answer....(C)
Explanation:
hope this helps, the person above me is correct
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Calculate the number of atoms in 2.8 moles of silicon atoms
Answer:
1.686 × 10²⁴ atomsExplanation:
The number of silicon atoms can be found by using the formula
N = n × Lwhere n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
N = 2.8 × 6.02 × 10²³
We have the final answer as
1.686 × 10²⁴ silicon atomsHope this helps you
What type of reaction takes place
when propene is formed from
propanol?
A. Condensation
B. Dehydration
C. Hydration
D. Hydrolysis
E. Oxidation
Answer:
Hydration
Explanation:
* 2-propanol is converted to propene using heated alumina beads as the catalyst. The product gas is purified with a dry ice–propanol cold trap.
* the propene is hydrogenated to propane using a palladium catalyst in nearly 100% yield
how many bonds can sodium form
it exists as atom or ion but not as sodium molecule. So there is no any sodium sodium bonding between two sodium atoms. Sodium combines with other element or group to form compounds of sodium like sodium chloride ,sodium carbonate ,sodium sulphate etc. Sodium has symbol Na and its atomic no. is 11 .
Answer:
[tex]\boxed{One\: Ionic\: Bond}[/tex]
Explanation:
For example, sodium, which is a metal, and chloride, a nonmetal, form an ionic bond to make NaCl.
Hope it helps!<3
Which of the following is not an advantage of asexual reproduction?
A. Quick
B. only involves one parent
C. genetic sameness
D. genetic variation
Answer:
a
Explanation:
Question 3
The element with electron configuration 1s^2 2s^s 2p^6 3s^2 3p^2
S (Z = 16).
Mg (Z = 12).
C (Z = 6).
Si (Z = 14).
Answer:
I'm on the same question as you