# Search results

1. ### RE: variation

oic. thanks a lot. y is directly proportional to x2 x is increased by 100% find the percentage increase in y. so, y= k x2 then y= k x2 y=k 4 x2 so 4 x2 is already increased by 100%? then to find k which is y=k 4 x2 k= y/ 4 x2 find the percentage increase in y, so what i...
2. ### Find the percentage increase in y

y is directly proportional to x2. x is increased by 100%. Find the percentage increase in y. so, y=k x2 y= k (100 + x2) then i went to find the k, which is k= y/ (100 + x2) so i put back the k which i found into y= k (100 + x2) which is : y= y/(100 + x2) (100 + x2) them im...
3. ### Magnesium nitrate is a salt?

why magnesium nitrate does not react with sulphuric acid?:confused: can somebody help answering? thank you.:smile:
4. ### I need help on Speed of reaction

i need help on the calculation speed of reaction. How to determine whether it is endothermic or exothermic? somebody help pls. thanks lotsa:biggrin:
5. ### Physical properties

does metals has the following? Qns. high melting point, insoluble in water, conduct electricity in solid and liquid. may i know what's the physical properties of covalent compound? do they have low melting point? does ionic compound has high melting point ? can somebody correct...
6. ### Ionic compound

A list of compounds and their formulae are given below. Select those compounds that are IONIC. (choose all that Apply) A.)sulfuric acid H2SO4 B.) glucose C6H12O6 C.) sodium ethanoate CH3COONa D.) magnesium Sulfate MgSO4 E.) Propyl ethanoate CH3COOC3H7 i've chosen C and D. am i...
7. ### Chemistry Compound and molecule?

Only 3 statements are correct. A.) Water is a compound and exist as molecules at rtp. B.) Magnesium chloride is a molecule but not a compound. C.) At rtp, nitrogen exist as diatomic molecules. D.) Rubidium Oxide is a compound but not considered a molecule. E.) Oxygen gas is classified as a...
8. ### Elements, Compounds and Mixture

Which 2 groups of substances below contain 1 element, 1 compound and 1 mixture? pick 2 groups. A.) Gold, sodium chloride, steel B.) oxygen, iodine, air C.) methane, iron(III)chloride, sea-water D.) Helium, carbon(IV) oxide, mixed dessert E.) Bronze, stainless steel, nitrogen(IV)oxide i...
9. ### Properties Of ionic and covalent

Which properties concerning ionic compounds and covalent molecules are INCORRECT? pick 3 statements. A.) All ionic compounds are soluble in water. B.) All covalent molecules are INSOLUBLE in water. C.) Covalent molecules are usually soluble in organic solvents. D.) Covalent molecules have...
10. ### Group VI elements

Which of the following statements are CORRECT, concerning any elements in Group VI of the periodic table? pick out 3 CORRECT statements. A.) It has 6 valence electrons. B.) It has 6 electron shells. C.) It can form an ion of charge -2. D.) It has valency value of 2. E.) It will lose 2...
11. ### Chemistry mixture help

Regarding about the Mixture. Question goes: Statement concerning a mixture is INCORRECT. only one statement is incorrect. which one? A.) It has a variable composition by mass. B.)It boils over a range of temperatures. C.)It has properties that are entirely different from those of its...
12. ### Nucleus of an atom contains only neutrons and protons?

thanks hootenanny:wink: im not sure if my teacher had set this question wrongly or not? because im finding it hard to answer. the question goes: TWO statement below are INCORRECT. which are these 2 statements? A.) the nucleus of an atom contains only neutrons and protons. B.)The mass...
13. ### Is there any energy involved in the formation of mixture?

:confused: 1.) Is it possible for the number of neutrons and the number of protons to be equal? 2.) Is it possible for the mass number(nucleon number) and atomic number(proton number) of an atom to be equal? 3.) Is there any energy invovled in the formation of mixture? 4.) does...