Answer: d. 47.4%
What is the percent yield of lithium hydroxide from a reaction of 7.40 g of lithium with 10.2 g of water? The actual yield was measured to be 12.1 g.
When a hydrate is heated to high temperatures, what is generally the product?
Answer:
anhydrous compound
Heating a hydrate leads to an endothermic reaction that produces a residue known as the anhydrous compound. This compound is different in structure, texture and even color in some cases, from its parent hydrate.
Warming a hydrate prompts an endothermic response that creates a buildup known as the anhydrous compound. This compound is distinctive in structure, surface and even shading now and again, from its parent hydrate.
Drug designers are usually
Where are electrons located? (Use the correct term not just the location(
Answer: electrons are found outside the nucleus.
Explanation:
*HELP ASAP PLEASE !!*
What effect does the value for 20°C in trial 3 have on the data's measures of
central tendency?
A. The median will be lower than the mean and mode.
B. The mean will be lower than the median and mode.
C. The median will be higher than the mean and mode.
O
D. The mean will be higher than the median and mode.
Answer:
D
Explanation:
I look the quiz
Answer:
Its The mean will be higher than the median and mode.
Explanation:
I took the quiz, be careful because some times the answers are in other order.
Seeds are often found on which part of a gymnosperm?
O branch
O leaf
O cone
O stem
Answer:
I believe the answer is b
Although Ionic Compounds are described by small whole # ratios like MgCl2 combining in a 1:2 ratio, in reality the ions typically combine in much larger ratios like a _______ : _______ ratio
# of molecules/atoms in each (show your work)
a. 0.572 moles of Al
b. 1.45x10² moles of SO2
c. 6.25 moles of Ca (OH)2
d. 0.0024 moles of CO2
Answer:
3.44× 10²³ atoms
8.73× 10²⁵ molecules
37.64 × 10²³ molecules
0.014 × 10²³ molecules
Explanation:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
a) 0.572 moles of Al:
1 mole = 6.022 × 10²³ atoms
0.572 mol × 6.022 × 10²³ atoms / 1 mol
3.44× 10²³ atoms
b) 1.45× 10² moles of SO₂:
1 mole = 6.022 × 10²³ molecules
1.45 mol × 10² × 6.022 × 10²³ molecules / 1 mol
8.73× 10²⁵ molecules
c) 6.25 moles of Ca(OH)₂
1 mole = 6.022 × 10²³ molecules
6.25 mol × 6.022 × 10²³ molecules / 1 mol
37.64 × 10²³ molecules
d) 0.0024 moles of CO₂
1 mole = 6.022 × 10²³ molecules
0.0024 mol × 6.022 × 10²³ molecules / 1 mol
0.014 × 10²³ molecules
need answer to this question asap. it is worth 10 points
the molar ratio of carbon to hydrogen of a volatile liquid compound is 1.2:0.12 of the liquid. on evaporation at s.t.p gave 32cm3 of vapour. what is the molecular formula of the liquid
The molecular formula of the liquid : C₆H₁₂
Further explanationGiven
molar ratio C H = 1.2 : 0.12
0.12 g at STP gave 32 cm³(0.032 L)
Required
The molecular formula
Solution
At STP, 1 mol = 22.4 L, so for 0.032 L :
mol = 0.032 : 22.4
mol = 0.00143
Molar mass (M) of liquid :
M = mass : mol
M = 0.12 g : 0.00143 mol
M = 83.92≈84 g/mol
C : H = 1 : 2
(CH₂)n=84
(12+2.1)n=84
(14)n=84
n=6
(CH₂)₆=C₆H₁₂
A substance is found to have a density of 2.4 g/ml and weighs about 100g. What is its volume?
Answer:
41.67 mLExplanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} \\[/tex]
From the question we have
[tex]density = \frac{100}{2.4} \\ = 41.66666...[/tex]
We have the final answer as
41.67 mLHope this helps you
Fresh water is distributed blank in both time and space.
Answer:
unevenly
Explanation:
Fresh water is distributed unevenly in both time and space.
A sample of methane gas (CH4 (g)) having a volume of 2.8 L at 25oC and 1.65 atm was mixed with a sample of oxygen gas having a volume of 35 L at 31oC and 1.25 atm. The mixture was then ignited to form carbon dioxide and water. Calculate the volume of CO2 formed at a pressure of 2.5 atm and a temperature of 125oC.
Answer:
2.47 L
Explanation:
The first thing we do is to write the balanced equation, which is.
CH4(g) + 2O2(g) --> CO2(g) + 2H2O(g)
Now, using ideal gas equation, we see that
PV = nRT
moles of methane
where P is the pressure, 1.65 atm
V is the volume, 2.8 L
R is the ideal gas constant, 0.0821
T is the temperature in Kelvin, 25 + 273 = 298 K
n = PV/RT
n of methane = 1.65 * 2.8 / 0.0821 * 298
n of methane = 4.62 / 24.47
n of methane = 0.189 mole
moles of O2:
PV = nRT
where P is the pressure 1.25 atm
V is the volume, 35 L
R is the ideal gas constant, 0.0821 L
T is the temperature, 31 + 273 = 304 K
n of O2 = 1.25 * 35 / 0.0821 * 304
n of O2 = 43.75 / 24.96
n of O2 = 1.75 mol
from the equation, the molar ratio between O2 and CH4 is 2:1, so therefore
no of moles of O2 = 2 * .0189 moles of methane = 0.378 mole
when 1 mole of CH4 --> 1 mole of CO2
1 mol of CO2 --> 22.4 L CO2
volume of CO2 at STP = [(0.189 moles of CH4 /1) * (1 mol of CO2)] / [(1 mole CH4) * (22.4L CO2)/(1 mol of CO2)] = 4.23 L
Next, we use the formula
P1V1 /T1 = P2V2/T2
where
P1 = 1 atm
V1 = 4.23 L
T1 = 273
P2 = 2.5 atm
T2 = 125 + 273 = 398 K, making V2 subject of formula, we have
V2 = P1V1T2 / T1P2
V2 = 1 atm * 4.23 L * 398 / 273 * 2.5 atm
V2 = 1683.54 / 682.5
V2 = 2.47 L
1.Which is the lowest level of organization for the system in a human
body? *
brain cell
nerve tissue
Answer:
brain cell
Explanation:
hope this helps :)
Predict what would happen if you prepared food on a countertop that had just
been cleaned with chemicals but was not completely rinsed off.
Answer:
there would be chemicals on the food.
Explanation: Hope this helps :)
What is the ion symbol for Lithium?
Answer:
Lithium is an alkali metal. The symbol for lithium element is ‘Li’. It belongs to group 1 of periodic table. Its electronic configuration is 1s2 2s1. It has one valence electron. So it loses one electron to attain stable configuration. Hence the symbol for lithium ion is ‘Li+’.
Explanation:
ithium is a chemical element with the symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the lightest metal and the lightest solid element. Like all alkali metals, lithium is highly reactive and flammable, and must be stored in mineral oil. When cut, it exhibits a metallic luster, but moist air corrodes it quickly to a dull silvery gray, then black tarnish. It never occurs freely in nature, but only in compounds, such as pegmatitic minerals, which were once the main source of lithium. Due to its solubility as an ion, it is present in ocean water and is commonly obtained from brines. Lithium metal is isolated electrolytically from a mixture of lithium chloride and potassium chloride.
What is the "major drawback" to using word equations?
a) Word equations can't be translated to other
languages.
b) Words are not specific enough to identify
chemicals.
C) Word equations are not quantitative.
Answer:
C
Explanation:
they can be put in other languages
they are literally the name of the chemical
they don't show quantity
The "major drawback" to using word equations is that they are not quantitative. Option C is correct.
Chemical reactions are written in word equations to give a clear and concise understanding of the reaction taking place. However, word equations are not quantitative. A equation is a way of representing a chemical reaction using words. It identifies the reactants and products and their physical states as well as the condition under which the reaction is taking place.
For example, the word equation for the reaction between hydrogen gas and oxygen gas to produce water is:
Hydrogen gas + oxygen gas → water
Quantitative equations use chemical formulas, numbers and symbols to represent the reactants and products in a chemical reaction. They provide a quantitative understanding of the reaction in terms of the number of atoms and molecules involved.
Know more about equations:
https://brainly.com/question/29657983
#SPJ6
2. CHECK ALL THAT APPLY: Select the question(s) that will involve molar mass.
(1 Point)
How many atoms of lithium would be equal to 3.7 moles of lithium?
A substance consisting of 3.7 grams of beryllium fluoride would be equal to how many moles of beryllium
fluoride?
How many grams of sodium are equal to 1.5 moles of sodium?
If you had 5.6 moles of carbon dioxide, you would have how many liters of carbon dioxide?
Answer:
A substance consisting of 3.7 grams of beryllium fluoride would be equal to how many moles of beryllium fluoride?
How many grams of sodium are equal to 1.5 moles of sodium?
Explanation:
The molar mass is related to number of moles and mass of an element or compound.
Using the expression:
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
For any problem, where the number of moles is known, we can find the mass.
A substance consisting of 3.7 grams of beryllium fluoride would be equal to how many moles of beryllium fluoride?
Here we know the mass, we simply use the molar mass to find the number of moles.
How many grams of sodium are equal to 1.5 moles of sodium?
Here number of moles is given, we use the molar mass to find the mass of the sodium given
Which type of offspring are most likely the result of sexual reproduction?
O A. diverse offspring with half of the genes from each parent
o
B. identical offspring with half the genes from each parent
O
C. identical offspring with the same genes as the parent
OD. diverse offspring with the same genes as the parent
Answer:
C
Explanation:
C.OD diverse offspring with the same genes as the parent
Organs that work to remove waste products are___.
A. Lungs
B. Kidneys
C. Liver
D. Skin
Answer:
Excretion is the process of removing wastes from the body. Organs of the excretory system include the kidneys, large intestine, skin, and lungs.
The excretory system removes metabolic wastes from the body. The major organs of excretion are the kidneys, a pair of bean-shaped organs located below the liver. The kidneys filter blood and regulate water balance in the body
Made up of the protons and neutrons, this part or the atom contains nearly all the mass of the atom
Answer:
The nucleus
Explanation:
*CHEMISTRY*
During ionic bonding, there must be a chemical interaction between....
O metallic elements, only
O nonmetallic elements, only
O one metallic and one nonmetallic element, only
O metalloids ,only
what type of energy warms earths surface?
A. Solar energy
B. Gravitational energy
C. Nuclear energy
D. Thermal energy
a. solar energy
the earth is warmed by the sun, which is solar (or infrared).
Which group of compounds has a –OH functional group?
aldehydes
esters
carboxyl acids
alcohols
What is the concentration of a solution containing:
a 4 moles in 2 dm of solution?
b 0.3 moles in 200 cm3 of solution?
a. 2 M
b. 1.5 M
Further explanationGiven
a 4 moles in 2 dm of solution?
b 0.3 moles in 200 cm3 of solution
Required
The concentration of a solution
Solution
Molarity shows the number of moles of solute in every 1 liter of solution or mmol in each ml of solution
Can be formulated :
[tex]\large \boxed {\bold {M ~ = ~ \dfrac {n} {V}}}[/tex]
a.
moles(n) = 4
volume(V)=2 L solution
M = 4 : 2 = 2
b.
moles(n)=0.3
volume(V)=200 cm3 = 0.2 L
M = 0.3 : 0.2 = 1.5
What does the image below represent?
Answer:
I think it's the electron dot structure for oxygen
What effect does altitude have on climate?
Answer:
Locations at a higher altitude have colder temperatures
Explanation:
brainliest please
What is “the process in which electrons are rearranged without direct contact”???
Answer:
Induction
Explanation:
When a body is brought in contact with another, electrons are rearranged by contact.
When a body is rubbed against one another, charging by friction occurs.
The process whereby electrons are rearranged without direct contact with one another is called induction.
By induction electrons can get charged without them having to be in contact with one another.
When a charged body is brought to the vicinity of the electrons, either an attraction or repulsion force is set up. Similar charges causes repulsion If a negatively charged body is brought near the electrons, there would be heavy repulsion and the electrons would be forced to rearranged. This effect is product as a result of a force field.which one of the following is different from the others A .HCl B. HF C. HBr D. HI
Answer:
D.HI
Explanation:
because this is the most different
balence the following equation :
_____ MgO + _____ Li2SO4 -----------> ______ MgSO4 + ______ Li2O
Answer:
it's already Balanced
MgO + Li2SO4 ---------✓ MgSO4 + Li2O
Winter is coming and it's time to make sure you have the right amount of antifreeze
in your car. The best mixture of antifreeze and water is 50% antifreeze with 50%
water. The cooling system in your car has a mixture of 6.00 L water with 6.00 L of
ethylene glycol (antifreeze).
What is the molality of that solution?
The chemical formula for ethylene glycol is C2H602 and its density is 1.1132 g/cm3. (
Hint- use the density to find the mass of 6.0 L of C2H6O2, and remember that 1.0cm3
= 1.0 mL and that 1.0 L of water = 1.0 kg)
The molality of the solution = 17.93 m
Further explanationGiven
6.00 L water with 6.00 L of ethylene glycol(ρ=1.1132 g/cm³= 1.1132 kg/L)
Required
The molality
Solution
molality = mol of solute/ 1 kg solvent
mol of solute = mol of ethylene glycol
mass of ethylene glycol := volume x density
= 6 L x 1.1132 kg/L
= 6.6792 kg
= 6679.2 g
mol of ethylene glycol (MW=62.07 g/mol)=mass : MW
=6679.2 : 62.07
=107.608
mass of water6 L water = 6 kg water(ρ= 1 kg/L)
molality[tex]\tt =\dfrac{107.608}{6}=17.93~m[/tex]
A compound is a pure substance made up of two or more different atoms joined by chemical bonds. Consider the composition of the air in Earth’s atmosphere. Which of the components of air is a compound? (Hint: refer back to your elements notes) How do you know?
Answer:
Carbon dioxide is a compound
Explanation:
It is formed by chemical combination of carbon and oxygen atoms