To convert a temperature from Fahrenheit (°F) to Celsius (°C), you can use the following formula:

C=5/9×(F−32)

Given that the measured temperature is 200°F, let's substitute this value into the formula:

C=5/9×(200−32)

C=5/9×168

C≈840/9

C≈93.33°

So, the correct answer is:

(c) 93.3°C

Number of moles=Mass/Molar mass

Number of moles=5.85 g/58.44g

Number of moles≈0.1 molNumber of moles≈0.1mol

Next, we need to convert the volume of the solution from milliliters (mL) to liters (L):

V=500 mL/1000 mL
V=0.5 L

Now, we can calculate the molarity:

M=0.1 mol/0.5 L

M=0.2 mol/L

So, the correct answer is:

(c) 0.2 mol L^-1

First, let's calculate the number of moles for each given mass of the elements using the formula:

Number of moles=Given massMolar massNumber of moles=Molar massGiven mass

Then, we can calculate the number of atoms for each element using the formula:

Number of atoms=Number of moles×Avogadro’s numberNumber of atoms=Number of moles×Avogadro’s number

Now, let's perform the calculations for each option:

(a) For 4g He: Number of moles=4 g4.0026 g/mol≈0.9996 molNumber of moles=4.0026g/mol4g≈0.9996mol Number of atoms=0.9996×6.022×1023≈6.027×1023Number of atoms=0.9996×6.022×1023≈6.027×1023

(b) For 46g Na: Number of moles=46 g22.9898 g/mol≈2.0003 molNumber of moles=22.9898g/mol46g≈2.0003mol Number of atoms=2.0003×6.022×1023≈1.2042×1024Number of atoms=2.0003×6.022×1023≈1.2042×1024

(c) For 0.40g Ca: Number of moles=0.40 g40.078 g/mol≈0.009978 molNumber of moles=40.078g/mol0.40g≈0.009978mol Number of atoms=0.009978×6.022×1023≈6.0085×1021Number of atoms=0.009978×6.022×1023≈6.0085×1021

(d) For 12g He: Number of moles=12 g4.0026 g/mol≈2.996 molNumber of moles=4.0026g/mol12g≈2.996mol Number of atoms=2.996×6.022×1023≈1.8026×1024Number of atoms=2.996×6.022×1023≈1.8026×1024

Comparing the calculated number of atoms for each option, we find that:

The greatest number of atoms is present in 12 g He (Option d).

To find the number of molecules of H2SO4H2SO4 present in 100 mL of a 0.02 M H2SO4H2SO4 solution, we need to first calculate the number of moles of H2SO4H2SO4 present in the solution using the given concentration.

Given:

• Concentration of H2SO4H2SO4 solution = 0.02 M
• Volume of H2SO4H2SO4 solution = 100 mL = 0.1 L

Using the formula for molarity, M=molesvolume (in L)M=volume (in L)moles, we can rearrange it to find the number of moles:

moles=M×volume (in L)moles=M×volume (in L)

moles=0.02 mol/L×0.1 Lmoles=0.02mol/L×0.1L

moles=0.002 molmoles=0.002mol

Now, to find the number of molecules, we'll use Avogadro's number, 6.022×10236.022×1023 molecules/mol:

Number of molecules=moles×Avogadro’s numberNumber of molecules=moles×Avogadro’s number

Number of molecules=0.002 mol×6.022×1023 molecules/molNumber of molecules=0.002mol×6.022×1023molecules/mol

Number of molecules=1.2044×1021 moleculesNumber of molecules=1.2044×1021molecules

So, the correct answer is:

(a) 1.2044×10211.2044×1021 molecules