A particular brand of beef jerky contains 0.0552% sodium nitrite by mass and is sold in an 8.00-oz bag. What mass of sodium does the sodium nitrite contribute to the sodium content of the bag of beef jerky?

Video transcript

Welcome back everyone in this example, we have a 12 ounce pack of ham that consists of .0515% of sodium nitrite by mass. And we need to calculate the mass of sodium contributed by the sodium nitrate in the ham. So what we're going to start out with is our recognition that we are given our sample being the ham in units of ounces. However, our final unit needs to be mass. So we want to go ahead and convert from ounces to grams. So we have 12 ounces of ham according to the prompt. And we're going to recall the conversion factor that for one ounce we have an equivalent of 28.35 g. So this allows us to cancel out our units of ounces leaving us with grams which is what we want. And this is going to give us our massive ham equal to 340. g of ham. And now that we have our massive ham, we want to utilize the information from the prompt, being our percent by mass of sodium nitrite in the ham, which is this value here. And so we should understand that this decimal value or percentage value 0.0515% of our sodium nitrite is equivalent to our mass of sodium nitrite Divided by our mass of Ham. So that above would be what we calculated as 340.2 g of our ham. So this fraction times 100 is equivalent to our percent by mass given in the prompt. And so we want to solve for mass of sodium nitrite. And so in order to do so, we want to go ahead and multiply both sides by our denominator. 340.2 g. This allows us to cancel out our denominator here and what we would get is 17.52, is equal to our grams of sodium nitrite. Multiplied by 100. And so we want to divide now both sides by 100. And so this gives us our mass of sodium nitrite Equal to 0.1752 g of sodium nitrite. And sorry, that's grams of sodium nitrite. And now that we have our value of sodium nitrate and grams, we can finally focus on going from grams of sodium nitrite, two g of our sodium for our final answer. And so beginning out are still geometry, We have our value. We just found 0.1752 g of sodium nitrate nitrite. And because we want to cancel out grams of sodium nitrite to get two g of sodium, we're going to recall from the periodic table or molar mass of sodium nitrite, which we see has a value of 69.0 g of sodium nitrite Equal to one mole of sodium nitrate. So now we can cancel out our grams of sodium nitrite. And now we are left with multi sodium nitrite where we need to recall our multiple conversion factor, where we see that in one mole of sodium nitrite. When we look at the molecular formula and count the amount of nitrogen we have. We have 12 moles of nitrogen. So we would plug that in a numerator. We have two moles of nitrogen in our one mole of sodium nitrite. And correction this is for sodium because the prompt is asking for sodium. So apologies. We want to look at the amount of sodium we have and we see we have one mole of sodium here because we just have N. A. For our sodium in our formula for sodium nitrite. So that's one mole of sodium in our numerator. And so now we can go ahead and cancel out our moles of sodium nitrite. And now we are with moles of sodium where we can focus on going from moles of sodium two g of sodium. So we would recall from the periodic table that we have a molar mass of 22. g of sodium equal to one mole of sodium. So now we can get rid of our moles of sodium And we're left with grams of our sodium as our final unit, which is what we want to enter this prompt. And this is going to give us a value equal to 0.058g of sodium contributed from our sodium nitrite. And so for our final answer, this is going to correspond to choice C. And our multiple choice. So what's highlighted in yellow here represents our final answer to complete this example. So I hope that everything that I wrote was clear. If you have any questions, please leave them down below and I will see everyone in the next practice video.