What are some really cool working science models I can prepare for my school science exhibition?
In this question the age of the participant and the interest area is not defined so i will suggest a few projects under heading of sub- subjects.BiologyEffect of light/sound on the growth of a plantworking model of heartworking model of kidney.Physicsautomatic night lightoersted experimentrenewable sources of energyChemistryelectrolysis of watermake potash alumsimple galvainic celPresenting the project is equally important, Find some great ideas on presentation here. Presentation ideas on school projects - #1 Site to buy school projects.Most important have fun while doing it.
PLEASE HELP! CHEMISTRY HOMEWORK!?
Question 1: Answer: 2 NaN3(s) --> 2 Na(s) + 3 N2(g) Question 2: One mole of any gas at STP occupies 22.4 liters of volume. Since the gas is collected at 24 °C and 3.10 atm of pressure, we should correct its volume to STP conditions using a combined gas law equation: [(P1)(V1)] / (T1) = [(P2)(V2)] / (T2) or V2 = [(P1)(V1)(T2)] / [(T1)(P2) At car conditions: V1 = 52.0 L P1 = 3.10 atm T1 = 24 °C + 273 = 297 K At STP: V2 = ? P2 = 1.00 atm T2 = 273 K V2 = [(3.10 atm)(52.0 L)(273 K)] / [(297 K)(1.00 atm) V2 = 148 L Now we can calculate the number of moles of nitrogen that must be generated by dividing its volume as STP by the molar volume of 22.4 L. (148 L) / (22.4 L/mol) = 6.61 mol Answer: 6.61 moles of nitrogen must be generated to inflate 52.0 liter bag at 24°C and 3.10 atmosphere of pressure. Question 3: 2 NaN3(s) --> 2 Na(s) + 3 N2(g) Let us use dimensional analysis and equation coefficients to convert 6.61 moles of nitrogen to moles of sodium azide. You will need the following equality to set up the conversion factor: 3 mol N2 = 2 mol NaN3 [(6.61 mol N2)/1][(2 mol NaN3)/(3 mol N2)] = 4.40 mol NaN3 Answer: 4.40 moles of sodium azide is required to generate this much nitrogen. Question 4: To convert 4.40 moles of sodium azide to grams of sodium azide, we must multiply 4.40 moles by the mole mass of sodium azide. 1 x Na = 1 x 22.99 = 22.99 3 x N = 3 x 14.007 = 42.021 total = 65.011 g/mol (4.40 mol NaN3)(65.011 g/mol) = 286 g NaN3 Answer: 286 g of sodium azide is required. Question 5: Answer: 10 Na(s) + 2 KNO3(s) --> K2O(s) + 5 Na2O + N2(g)
How do I pass Nios on demand exam in physics and chemistry?
Its not that complicated. Just enroll to the nearest NIOS center. Ensure that it is authorized by the NIOS headquarters, Noida. You can check in the NIOS official website regarding the authenticity of that center. You can also take admission online directly from the NIOS website. Having said the above points, the reason for appearing for NIOS on-demand exam is important- that whether you want to give the on-demand exam to save a year or just for passing with better marks. If you are thinking about saving a year, and if you've failed in 1 or more subjects, it is recommended to appear for the on-demand exam. The syllabus of NIOS is similar to that of CBSE, both being administered by the Ministry of HRD, India. So, just check the syllabus & exam pattern before thinking about the exam. And if you are a new student who has not appeared in the class-12 board exam, I would recommend sitting for the NIOS regular board exam which will be conducted in October. Also, to appear in the on-demand exam, one has to show the hall ticket/admit card of any recognized board to be eligible for the on-demand exam. Now, coming to your question of passing in Physics & Chemistry exam, it is not that difficult. Just use cautiously whatever the time you are left with. Do not try to learn new, complicated topics now. Instead, focus more on all the learned topics to extract maximum marks out of them. See the topic-wise marks distribution so that you can get an idea of the topics which carry good marks. Refer to the previous years papers, available in the NIOS website, to understand the pattern. For any more clarifications, feel free to ask me. Visit www.nios.ac.in for more info. All the very best!!!!
The Apollo lunar landing module used a fuel composed of hydrazine (N2H4) and dinitrogen tetroxide (N2O4).?
1) 2 N2H4 + N2O4 → 3 N2 + 4 H2O 2) (5.0 g N2H4) / (32.04523 g N2H4/mol) x (3 mol N2/ 2 mol N2H4) x (28.01344 g N2/mol) = 6.6 g N2 (5.0 g N2H4) / (32.04523 g N2H4/mol) x (4 mol H2O / 2 mol N2H4) x (18.01532 g H2O/mol) = 5.6 g H2O Total: 6.6 g N2 + 5.6 g H2O = 12.2 g nitrogen and water c) (9.845 g Fe) / (55.8452 g Fe/mol) x (6.022 x 10^23 atoms/mol) = 1.062 x 10^23 atoms Fe
HELP ASAP!! solubility of gases in liquid in terms of kinetic-molecular theory.?
at higher temperature, the gas molecules have more kinetic energy, are moving faster, and they are more able to escape from the liquid.
How can I score more than 95% marks in class 12th science stream?
You can easily score 95% even if you start working now. (Just assuming you passed in half yearly with atleast 60%)I passed 12th last year only with 94.4% aggregate. And by this time(december), I just used to attend tuitions. No self study.I started taking BOARDS seriously only after boards datesheet was out. (1st week of jan)I'd just suggest you to mug up the NCERT books first.Take pre-boards seriously. As most of the time, your board practicals marks are awarded on the basis of pre-boards. Even externals also ask you about your pre-boards performance.Not only this, pre boards will tell you your current status about how much you're prepared for boards.So,make sure you get 30/30 in three of the practicals.Now, for theory examsFirst and foremost thing is to mug up NCERT books. Get through it. Boards paper constitutes direct questions from NCERT.For chemistry, NCERT book is more than enough. I'd not suggest any reference or previous year books.For maths, the question paper will surely constitute of 50% direct NCERT questions.But in maths, you need to do previous year papers. For this, get U-like book and solve each and every paper. This will help in managing time to complete paper in 3 hours. Time management is must in MATHS boards. For physics, it is going to be a little tough as compared to other subjects. But if you're thorough with concepts,90+ is easy to score Practice each derivation. Get through the numericals. For physics too, purchase U-like and simply solve all the solved papers.For english, Time management is equally important. You don't really need to use fancy words in writing section. Be direct and underline important points. Do the character sketch for novel section.I had physical education as 5th subject. So, the textbook was enough to fetch me 96/100.Rest, goodluck for your boards. I hope you get 95+ in your boards so as to answer calls of your relatives with pride on the result day.This is only where this percentage is going to help. :D
What does C.O.R.M.S. stand for in the IGCSE Biology mark scheme?
C - control: always include a control in your experiment, eg for the light intensity leaf experiment have an empty test tube with just some indicator in it... O - organism: what organisms will be involved and what similarities do they need to have eg. same sex, age, health, ect R - repetition: how many repeats do you do to make it more practical? M - measurement: what do you plan to measure? eg growth length temperature weight size ect. S - standard: what do you need to keep the same? eg time, diet, oxygen, light intensities pH ect got the igcse tomorrow too, was looking for someone to answer the same question but have suddenly found my notes! have you learned al the experiments? also whats the experiment to "demonstrate the evolution of carbon dioxide and heat from respiring seeds and other living organisms"?? or what page is it on in longman? good luck tomorrow
Is Xam Idea enough to get a 95% in the CBSE for class 12?
It's a risk worth taking ( I have used the word risk and I mean it because there is a 10% chance that CBSE changes the question pattern) .I'll prefer xam idea or together with( another exam oriented book ) for my 12th board preparation . Make sure that you know the basics from NCERT text and then go for these exam orientated books . Its better to refer these books ( or completely depend on this book) from mid November . If CBSE do not change the question pattern , 95 % should be a cakewalk for anybody who is thorough with XAM IDEA or together with ( I was lucky enough to get a 96.8 percentage 2 years ago and I did give more importance to together with than NCERT )Thanks