Answer:
B)As you go from left to right, reactivity of metals increases. As you go down in a group, reactivity of metals decreases.
Explanation:
reactivity of metals can be explained as how it can easily lose electron, i.e oxidize as well as reaction with non-metals.
There are factors that influence the reactivity of metals such as
1)atomic radius
2)nuclear charge
3)shielding effect
4) The sublevel arrangement of electrons
In the periodic table,the group 1, known as alkali metals, are the most reactive metals
Therefore, as we from left to right, reactivity of metals increases. As we move down in a group, reactivity of metals decreases.
Answer:
(B) Her results are both precise and accurate.
Explanation:
In Chemistry, Accuracy refers to how close a measurement is to it's standard value or known value. On the other hand, Precision means how close two measurement are to each other regardless whether the results are accurate or not.
In the above question, all the above results are very close to each other. That's why the results are Precise to each other. All the results are close enough to the actual value of the experiment. That's why the result are also accurate.
Answer:
0.0554 moles of NaCl are produced from the reaction of 1.67*10²² molecules of Na₂CO₃ with excess HCl.
Explanation:
The balanced reaction is:
Na₂CO₃ + 2 HCl → 2 NaCl + CO₂ + H₂O
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of each compound participate in the reaction:
- Na₂CO₃: 1 mole
- HCl: 2 moles
- NaCl: 2 moles
- CO₂: 1 mole
- H₂O: 1 mole
On the other hand, Avogadro's Number is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023*10²³ particles per mole. Avogadro's number applies to any substance.
In this case, you can apply the following rule of three: if 6.023*10²³ molecules of Na₂CO₃ are contained in 1 mole, 1.67*10²² molecules will be contained in how many moles?

amount of moles= 0.0277 moles
In this case, you can apply the following rule of three: if by stoichiometry 1 mole of Na₂CO₃ produces 2 moles of NaCl, 0.0277 moles of Na₂CO₃ will produce how many moles of NaCl?

amount of moles of NaCl= 0.0554 moles
<u><em>0.0554 moles of NaCl are produced from the reaction of 1.67*10²² molecules of Na₂CO₃ with excess HCl.</em></u>
The correct answer is 0.15.
We are aware that there is 0.05 mol of an unidentified hydrocarbon we will refer to as "X" and that its burning produces 6.6 g of carbon dioxide and 3.6 g of water.
These quantities might be converted to moles by applying the following formula:
amount= mass/ relative atomic mass
Thus, the following equation may be written for H2O: moles = 3.6 / 18 = 0.2 and for CO2: moles = 6.6 / 44 = 0.15.
0.05X + x'O2 = 0.15CO2 + 0.2H2O
This may be made simpler by dividing through by 0.05 (this step is likely to be the most helpful to you), resulting in:
1 x + x O2 = 3 co2 + 4 H2O
The hydrocarbon must have been the source of all the carbon in the carbon dioxide and all the hydrogen in the water.
Accordingly, 4 x 2 = 8 moles of H and 3 x 1 = 3 moles of C.
There are 3/1 = 3 Cs and 8/1 = 8 Hs in one X molecule.
This clearly identifies C3H8 or propane as the hydrocarbon X (dividing by 1 seems unnecessary, but it illustrates the process to use if there were more than one mol of X in the first equation).
To learn more about number of moles of carbon dioxide refer the link:
brainly.com/question/12723070
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