Answer:
Explanation:
We want to convert from moles of water to grams of water.
First, find the molar mass of water (H₂O) Look on the Periodic Table for the masses of hydrogen and oxygen.
- Hydrogen (H): 1.008 g/mol
- Oxygen (O): 15.999 g/mol
Next, add up the number of each element in water. The subscript of 2 comes after the H, so there are 2 moles of hydrogen.
- 2 Hydrogen: (1.008 g/mol*2) = 2.016 g/mol
Finally, add the molar mass of 2 hydrogen and 1 oxygen.
- 2.016 g/mol (2 Hydrogen) + 15.999 g/mol (1 oxygen)= 18.015 g/mol
Next, find the grams in 6.5 moles.
Use the molar mass we just found as a ratio.
We want to find the grams in 6.5 moles. We can multiply the ratio above by 6.5
Multiply. Note that the moles of H₂O will cancel each other out.
If we want to round to the technically correct significant figures, it would be 2 sig figs. The original measurement, 6.5, has 2 (6 and 5).
<h2>C. Chlorine (Cl)</h2><h2>This is your answer. </h2>
Answer:
Order of the cycle:
Step -1>>>>Step -4 >>>> Step -3 >>>>> step -2.
Explanation:
<u>Step -1:</u>
Carbon dioxide is taken in by plants during photosynthesis.
<u>Step -4;</u>
The animal eats a plant and uses its carbohydrates for energy.
<u>Step - 3</u>
The animal releases the carbon dioxide back into the atmosphere during respiration.
<u>Step -2</u>
The cycle repeats when the carbon stored in the atmosphere as carbon dioxide gas is taken in.
Therefore, order of the cycle is Step -1>>>>Step -4 >>>> Step -3 >>>>> step -2.
A. Boiling water is an example of physical change, whereas digesting food, breaking glass, and shoveling snow are not.
Answer:
0.134 moles of H₂ can be formed if a 3.25g sample of Mg reacts with excess HCl
Explanation:
The balanced reaction is:
Mg + 2 HCl → MgCl₂ + H₂
By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles react:
- Mg: 1 mole
- HCl: 2 moles
- MgCl₂: 1 mole
- H₂: 1 mole
Being:
- Mg: 24. 31 g/mole
- H: 1 g/mole
- Cl: 35.45 g/mole
the molar mass of the compounds participating in the reaction is:
- Mg: 24.31 g/mole
- HCl: 1 g/mole + 35.45 g/mole= 36.45 g/mole
- MgCl₂: 24.31 g/mole + 2*35.45 g/mole= 95.21 g/mole
- H₂: 2*1 g/mole= 2 g/mole
Then, by stoichiometry of the reaction, the following quantities of mass participate in the reaction:
- Mg: 1 mole* 24.31 g/mole= 24.31 g
- HCl: 2 moles* 36.45 g/mole= 72.9 g
- MgCl₂: 1 mole* 95.21 g/mole= 95.21 g
- H₂: 1 mole* 2 g/mole= 2 g
Then you can apply the following rule of three: if by stoichiometry 24.31 grams of Mg form 1 mole of H₂, 3.25 grams of Mg how many moles of H₂ will they form?
moles of H₂= 0.134
<u><em>0.134 moles of H₂ can be formed if a 3.25g sample of Mg reacts with excess HCl</em></u>
