Answer:
02- i think your welcome hope it helps
Answer:
Carbon is a chemical element, like hydrogen, oxygen, lead or any of the others in the periodic table. Carbon is a very abundant element. It exists in pure or nearly pure forms – such as diamonds and graphite – but can also combine with other elements to form molecules.
The answer is A hopefully it is ok ✅
Answer:
17.76g
Explanation:
We need to write a balanced chemical equation for the reaction:
2Al(OH)3 + 3Ca(NO3)2 ——> 3Ca(OH)2 + 2Al(NO3)3
In the reaction above, it can be seen that 2 moles of aluminum hydroxide yielded 3 moles of calcium hydroxide. This is the theoretical viewpoint.
Now we need to know what actually happened. We need to calculate the actual number of moles of aluminum hydroxide reacted l. We can get this by dividing the mass by the molar mass.
The molar mass of aluminum hydroxide is 27+ 3( 16+1)
= 27 + 51 = 78g/mol
The number of moles is thus: 12.55/78 = 0.16 moles
Now if 2 moles of aluminum hydroxide gave 3 moles of calcium hydroxide, 0.16moles will give : (0.16*3)/2 = 0.24moles
Now we can calculate the mass of calcium hydroxide formed. The mass of calcium hydroxide formed is the number of moles multiplied by the molar mass.
The molar mass of calcium hydroxide is; 40 + 2(17) = 74g/mol
The mass is thus =74 * 0.24 = 17.76g
Answer:
Jane has 2.77 * 10^20 molecules cholesterol in 1 dL of blood
Explanation:
<u>Step 1:</u> Given data
Molar mass of Cholesterol = 386.654 g/mol
Jane has a cholesterol of 178 mg/dL
<u>Step 2:</u> Calculate mass of cholsterol in 1 dL
178 mg/dL means in 1 dL she has 178 mg cholesterol or 0.178 grams
<u>Step 3</u>: Calculate number of moles of cholesterol
Number of moles = mass of cholesterol / molar mass of cholesterol
Number of moles = 0.178 grams / 386.654 g/mol = 4.6 * 10^-4 moles
<u>Step 4: </u>Calculate number of molecules
Number of molecules = 4.6 * 10^-4 mol * 6.022 *10^23 / mol = 2.77 * 10^20 molecules
Jane has 2.77 * 10^20 molecules cholesterol in 1 dL of blood