-
We need your support!
We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
Click here to Donate Now (View Announcement)
Search results
-
Chemistry: Post your doubts here!
Metals generally are, on an atomic scale, giant structures in which electrons in the outer shells of the metal atoms are free to move. Edit: Reference: https://www.chemguide.co.uk/atoms/structures/metals.html -
Chemistry: Post your doubts here!
The question asks for the ratio of masses of Gas X to Gas Y, but 0.174 is the ratio of masses of Gas Y to Gas X. Hence, we reciprocate it. -
Chemistry: Post your doubts here!
The answer is A. 2Mg(NO3)2 ------> 2MgO + 4NO2 + O2 The ratio of number of moles of NO2 (gas X) and O2 (gas Y) is 4:1 molar masses: X - 46 Y - 32 mass = (relative) number of moles * molar mass X - 46*4 = 184 Y - 32*1 = 32 32/184 = 0.174 Hence, the ratio of masses is 1/0.174 (A). -
A level Biology: Post your doubts here!
It is the point where the ratio of initial length to final length is 1, which is 0.45 moldm-3 sucrose concentration (from graph). -
Chemistry: Post your doubts here!
The answer is C. Boron trifluoride is trigonal planar because Boron has 3 valence electrons, while the nitrogen compound is tetrahedral because nitrogen has 5 electrons and only 3 were used for bonding, leaving a pair of unbonded electrons. The compounds form a coordinate bond after reacting... -
Physics: Post your doubts here!
B. Areas under the graph: Cheetah: 0.5*(15+17)(29) = 464 Antelope:0.5*(14+16)(25) = 375 Distance = 100+375-464 = 11m. -
Physics: Post your doubts here!
The answer is C. The only forces acting on an object after release are drag and gravity, but in this context drag can be ignored as the stone is thrown on the Moon, where there is no air resistance. Hence, there is no horizontal force but a single constant vertical force (gravity) acting...