Answer:
70%
Explanation:
To find the percent yield, you need to (1) convert grams HCl to moles (via molar mass from periodic table), then (2) convert moles HCl to moles H₂ (via mole-to-mole ratio from equation), then (3) calculate the percent yield H₂ (via percent yield equation).
Zn (s) + 2 HCl (aq) --> ZnCl₂ (aq) + 1 H₂ (g)
Molar Mass (HCl): 1.008 g/mole + 35.45 g/mole
Molar Mass (HCl) = 36.458 g/mole
125 g HCl 1 mole HCl 1 mole H₂
--------------- x ------------------ x ------------------ = 1.7 moles H₂
36.458 g 2 moles HCl
(actual yield / theoretical yield) x 100% = percent yield
theoretical/calculated yield = 1.7 moles H₂
actual yield = 1.2 moles H₂
(1.2 moles H₂ / 1.7 moles H₂) x 100% = 71%
Therefore, the best percent yield of hydrogen produced is 70%.
Number of significant figures will be 1.
Given:
weight of acetylsalicylic acid = 0. 4g
Significant figures are the digits of value which carry meaning towards the resolution of the measurement. They are also called significant figures in chemistry. All the experimental measurements have some kind of uncertainty associated with them.
When we convert 0.4g acetylsalicylic acid to mg we get value 400mg
when we convert 400mg to gram we get value of 0.4 gram
Since 0 before a decimal is not significant so there is only one significant figure that is 4.
<h3>How do you determine the number of significant figures?</h3>
- The zero to the left of a decimal value less than one is meaningless.
- All trailing zeros that are placeholders are meaningless.
- The presence of zeros between non-zero numbers is significant.
- Non-zero numbers are all significant.
- If a number contains more digits than the desired number of significant digits, it is rounded.
<h3>Why 'Hidden Figures' is so important?</h3>
It's an important story for a variety of reasons, and it comes at a time when people are looking to Hollywood more than ever to tell stories that represent them. Hidden Figures is that movie for many, and it's critical that everyone sees these women in action. This is why. This film tells a story that you've probably never heard before.
Learn more about Significant figure here:
<u><em>brainly.com/question/24491627</em></u>
#SPJ4
A science conclusion should simply have a statement identifying whether your experiment’s aim turned out to be true or false
The field of study that Christian Doppler's work influenced the most was about <u>light </u><u>waves.</u>
Hope it helps you.
