- Some questions frequently asked by houseowners : can someone please help me with average atomic mass?
♥ i'm very confused with what exactly avg. atomic mass and percent abundance is. here's a problem i just do not understand use the following to determine the average atomic mass of chlorine. two isotopes are known: chlorine-35 and chlorine-37. the relative abundance of chlorine-35 is 75.4%. what do i do? thanks.help with a chem question?
♥ ok so i have a test tomorrow and its on stociometry and limiting reagents. i got the stociometry part down but the limiting reagents are confusing the hell out of me. i searched on youtube but i cant find anything that i can understand. can i get an explanation on how to solve those type of problems? also i need help with this question: 1. consider the reaction: i(2)o(5) 5co ------------> 5co(2) i(2) a) 80 grams of of iodine(v) oxide reacts with 28 grams of carbon monoxide. determine the mass of iodine which could be produced. b) if in the above situation only .160 moles of iodine was produced i) what mass of iodine was produced ii) what percentage yield of iodine was produced? thanks sooooo muchi really need help please :'(?
♥ 27g of aluminium contain approximately 6.02x10^23 alumanium atoms. calculate the number of alumanium atoms in with following masses of alumanium a. 2.70g b. 1.00g c. 0.16g d.4.8lg i dont wan the answer i just want to understand the process of solving it step by step and if there is any youtube videos that exaplin this just put the link thank you so much!please help! 1. what is the definition of a mole?
♥ 2. write a balanced chemical equation for the reaction of sodium metal with water that produces diatomic hydrogen gas and sodium hydroxide (naoh). include all appropriate symbols. 3. how many atoms of sodium would be in one mole of sodium? 4. how much would one mole of water weigh? 5. how much would 2.3 molecules of water weigh? 6. if a beaker of water contains 123 grams of water, how many moles of water would this be? 7. in the balanced equation below, how many moles of iron iii chlorine (fecl3) would be made by the complete reaction of 1.2 moles of chlorine molecules? 2fe +3cl2 → 2 fecl3 8. in the reaction below, how many grams of sodium oxide (na2o) would be made by the complete reaction of 22.990 grams of sodium metal? 4 na o2 → 2 na2ohuge science test! help me please?
♥ alrightey. well i'm in 8th grade & we're taking a huge science exam (staar) in like two weeks. yikes! i'm an overall straight a student, but i'm suffering in science this year. i have no idea why i took advanced science, i guess i just thought i could handle all advanced classes. anyways; i'm good on evolution & the moon phases & pretty much everything else we learned in science except for the periodic table & atoms & bohr models & such. gahh! and chemistry is going to be the main focus on the test. oh joy. *sigh* can you explain any of these? ~how to find number of neutrons? ~difference between groups and columns and rows on periodic table? ~how to find number of valance electrons? ~how the heck do i read a simple bohr model? ~how do i know if an element is reactive or not by looking at the periodic table? ~what's the law of conservation of mass? okay, and if you're in the same grade as me, or have been and have any other tips to things that'll be on the test, i would so appreciate it! everyone in my class is like insanely smart in science & won't help me. :( i'm a really fast learner, i just didn't understand the way the teacher explained the subject. if you could help me, i'd give you best answer! thank you so much.