Answer:
jayfeather friend me
Explanation:
In a toasty kitchen, your dough may proof in as little as an hour (or less!). When the temperatures dip, it can take much longer—upwards of two or even three hours.
Na
Which term describes argon? *
(2 points)
alkali metal
halogen
transition metal
noble gas
Answer:
Argon is a noble gas
Hope this helps
Scientists say that the solar system formed from______.
Answer:
a rotating disk of dust and gases
Explanation:
brainliest?
Answer: scientists believe that the solar system was formed when a cloud of gas and dust in space was disturbed, maybe by the explosion of a nearby star (called a supernova). ... Squeezing made the cloud start to collapse, as gravity pulled the gas and dust together, forming a solar nebula.
Explanation:
HELPPPP DUE NOWWW (5)
Answer:
All the answers you chose are correct
Explanation:
Answer:
I cant see the fist question but all that you chose are correct
Explanation:
HURRY!!!! TIMED!!! WILL GIVE BRAINLIST!!!
A 10.0 g sample containing calcium carbonate (CaCO3) and an unreactive material was placed in excess hydrochloric acid, HCl. A reaction occurred, producing calcium chloride (CaCl2), water, and carbon dioxide. (a) write a balanced equation for the reaction (b) when the reaction was complete, 800 mL of carbon dioxide gas was collected. How many moles of calcium carbonate were used in the creation? (c) How many grams of CaCO3 were used? (d) If there was another contaminant in the sample that was not unreactive, would this have caused the percent yield of carbon dioxide to be higher, lower, or the same, explain your answer.
Explanation:
(a) write a balanced equation for the reaction
CaCO3 + HCl --> CaCl2 + H2O + CO2
The balanced equation is given as;
CaCO3 + 2HCl → CaCl2 + H2O + CO2
(b) when the reaction was complete, 800 mL of carbon dioxide gas was collected. How many moles of calcium carbonate were used in the creation?
From the balanced reaction;
1 mol of CaCO3 reacts to produce 1 mol of CO2
1 mol of CO2 = 22.4 L of CO2
This means;
1 mol of CaCO3 reacts to produce 22.4L of CO2
x mol would produce 800ml (0.8 L) of CO2
1 = 22.4
x = 0.8
x = 0.8 * 1 / 22.4 = 0.0357 mol
(c) How many grams of CaCO3 were used?
Mass = Number of moles * Molar mass
Molar mass of CaCO3 = 100.0869 g/mol
Mass = 0.0357 mol * 100.0869 g/mol = 3.57 g
(d) If there was another contaminant in the sample that was not un reactive, would this have caused the percent yield of carbon dioxide to be higher, lower, or the same, explain your answer.
The same
An un reactive contaminant in the sample is most likely a catalyst. Catalysts only affect the rate of reaction. They do not affect yields of products.
In chemical reactions, what does the principle of conservation of mass mean?
The nucleus of an atom contains ________________________________________.
Answer:
protons(positively charged) and the neutrons (no charge)
Explanation:
Answer:
The nucleus of an atom contains protons and neutrons.
Describe what happens to a liquid's molecules as it boils and changes into a gas.
Answer:
the particels becomes loose and wild, making gas happen when it is heated up
Liquids evaporate faster as they heat up and more particles have enough energy to break away. The particles need energy to overcome the attractions between them. At this point the liquid is boiling and turning to gas.
How many atoms of silver are in a bracelet that has a mass of 13.94 grams?
Number of Silver atoms : N = 7.8 x 10²² atoms
Further explanationGiven
mass of bracelet : 13.94 g
Required
Number of atoms
Solution
Assuming the bracelet consists entirely of silver
mol of silver :
= mass : molar mass
= 13.94 g : 107,8682 g/mol
= 0.129
Number of atoms :
N = n x No(No = Avogadro's number)
N = 0.129 x 6.02 x 10²³
N = 7.8 x 10²² atoms
Predict the empirical formulas of the ionic compounds formed from the following pairs of elements.
Mg and Cl
Cs and Br
Ga and I
Na and O
Sr and F
Ca and P
Explanation:
MgCl2
CsBr2
Na2O
SrF2
CaP2
what type of bond is Cl and Br?
Answer: Polar bond
Explanation:
why is it important for the appendages of an arthropod to be joined
Answer:
you mean "jointed." jointed appendages give arthropods much greater movement flexibility and range.
A 170.0 g sample of an unidentified compound contains 29.84 g sodium, 67.49
g chromium, and 72.67 g oxygen. What is the compound's empirical formula?
The empirical formula : Na₂Cr₂O₇
Further explanationGiven
170 g sample contains :
29.84 g sodium, 67.49 g chromium, and 72.67 g oxygen
Required
The compound's empirical formula
Solution
mol ratio of elements :
Na : 29.84 : 23 g/mol = 1.297
Cr : 67.49 : 51,9961 g/mol = 1.297
O : 72.67 : 16 g/mol = 4.54
Divide by 1.297
Na : Cr : O = 1 : 1 : 3.5 = 2 : 2 : 7
(25 points)Diesel fuel is used in the engines of the machines and trucks at the quarry. Which of these is the main energy transformation as the fuel is used by the engines
1 Electrical energy is converted to heat energy.
2 Heat energy is converted to potential energy.
3 Electrical energy is converted to kinetic energy.
4 Chemical energy is converted to kinetic energy.
Please help I will give brainliest
Answer:
Explanation:
c. - vaccine
b. - immunity
d. - phagocyte
f. - b cell
e. - t cells
a. active immunity
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Animals need various nutrients in order to live and grow. Nitrogen, for example, is a nutrient that is needed to form molecules found in genetic material. How do animals obtain nitrogen? A. They eat plants which have absorbed nitrogen from the soil. B. They create nitrogen in their bodies using other nutrients as building blocks. C. They breathe in and absorb nitrogen gas from the atmosphere. D. all of these
Answer:
It's A
Explanation:
Animals get the nitrogen they need by eating plants or other animals that contain nitrogen. When organisms die, their bodies decompose bringing the nitrogen into soil on land or into ocean water. Bacteria alter the nitrogen into a form that plants are able to use.
Find a periodic table and look for the atomic mass of sodium, Na. What is it?
Answer:
Atomic mass: 22.989769 u
Explanation:
2C4 H10 + 13O2 -→ 8CO2 + 10H2O If 356 moles of O2 are available to react, how many moles of CO2 will fom?
Answer:
Answer:
The mole ratio of C₄H₁₀ and CO₂ is 2 : 8, which simplifies to 1 : 4.
Explanation:
The mole ratio is the relative proportion of the moles of products or reactants that participate in the reaction according to the chemical equation.
The chemical equation given is:
2C₄H₁₀ + 13O₂ → 8CO₂ + 10H₂O
Once you check that the equation is balanced, you can set the mole ratios for all the reactants and products. The coefficients used in front of each reactant and product, in the balanced chemical equation, tells the mole ratios.
In this case, they are: 2 mol C₄H₁₀ : 13 mol O₂ : 8 mol CO₂ : 10 mol H₂O
Since you are asked about the mole ratio of C₄H₁₀ and CO₂ it is:
2 mol C₄H₁₀ : 8 mol CO₂ , which dividing by 2, simplifies to
1 mol C₄H₁₀ : 4 mol CO₂, or
1 : 2.
Explanation:
A student has a mixture of salt and iron filings.
Which property can the student use to separate the different parts of the mixture?
Answer:
aksksks
Explanation:ss
x
zxrkkrkrkkrkkrrkr
How many moles are in 7.8g of CaO?
This compound is also known as Calcium Oxide. The SI base unit for amount of substance is the mole. 1 grams CaO is equal to 0.017832495800447 mole. Note that rounding errors may occur, so always check the results.
Hope I helped :)
Toothpaste is an alkali. How could you use the toothpaste to show that red cabbage is an indicator?
Answer:
PUT THE TOOTHPAST ON CABBAGE AND CHECK IT OUT AFTER A DAY
Why is air considered a solution?
Answer:Air is a solution made up of many gases. ... There is more nitrogen than any other gas in air, so it is considered the solvent in an air solution.
Explanation:
WILL AWARD POINTS AND BRAINLIEST
Which of the following is an example of a compound?
Select all that apply
H20
F2
C2H6
Ag
Is the answer H2O and C2H6?
Someone please help I don't know if my answers are correct for this
Answer:
Your correct it is false
Suggest why we have discovered more elements today compared to our ancestors 50,000 years ago
Answer:
well, we have so much better and more tech and we are a lot smarter than we were before.
Explanation:
Answer:
We have way more advanced technology than our ancestors and we have a better idea of how the earth was millions of years ago.
Explanation:
does a high melting point mean the substance will melt faster or slower?
Answer:
slower...............
.
..
Answer:
it'll melt slower
Explanation:
because it needs to get to a higher temperature ig
What does the pattern in the image above represent?
OA. the phases of the Moon
OB. the patterns of the stars
OC. the seasons of the year
OD. the cycle of the Sun
Answer:
i dont know how to answer this because u need a pic of what you need
Explanation:
sorry just need a picture to confirm answer
Chem lab report is attached to the question plz help.
Answer: When I opened the doc it didn't work..
Explanation:
You are a nurse giving a patient 0.75 cc per minute of a drug cocktail intravenously . A cc is 1ml of a solution . If the patient needs thr iv for 2 hours how many liters of this solution will you need to prepare
Answer:
90 mL
0.09 Liters
Explanation:
Givens
1 cc of solution = 1 mL
0.75 cc / min needed to go in intravenously.
2 hours needed.
? Liters
Solution
1 hour = 60 minutes
1 hours = 2 * 60 = 120 minutes
rate = 0.75 cc/minute
Liters = rate * time
Liters = 0.75 cc * 120 minutes
Liters = 90 cc
That's not the answer.
1 Liter has 1000 mL or ccs
x Liter has 90 mL
Equation
1/x = 1000 / 90
Solution
Cross multiply
1000x = 90*1 Divide by 1000
x = 90/1000
x = 0.09 Liters.
Is energy part of the system or surrounding?
Answer:
Se Puede Traducir?
Explanation:
Mmm?
Answer:
i think it is surroundings
