Answer is: chemical.
Making a pancake from batter is chemical change (chemical reaction), because new substances are formed, the atoms are rearranged and the reaction is followed by an energy change.
Batter is thin dough that is poured into a pan to make pancakes.
In physical change, the same substance is present before and after the psysical change, just with different form or state of matter.
A contains 38.5 g of tin for each 12.3 g of fluorine:
<span>mole ratio: </span>
<span>(38.5 g)/(118.71 g/mol):(12.3 g)/(18.998 g/mol) = 0.324:0.647 = 1:2 ⇒ SnF₂ </span>
<span>B contains 56.5 g of tin for each 36.2 g of fluorine: </span>
<span>mole ratio: </span>
<span>(56.5 g)/(118.71 g/mol):(36.2 g)/(18.998 g/mol) = 0.476:1.905 = 1:4 ⇒ SnF₄
Thank you for posting your question here at brainly. I hope the answer will help you. Feel free to ask more questions.
</span>
2 O2 + CH4 CO2 + 2 H2O
<span>What mass of CH4 is required to completely react with 100 grams of O2? </span>
<span>mass CH4 = 100 g O2 x (1 mol O2 / 32 g) x (1 mol CH4 / 2 mol O2) x (16.05 g / 1 mol CH4) </span>
<span> 25 grams CH4
</span>