take 2 identical bowls filled with water.shine a spotlight on one and place one away from the spotlight in the same room. which shows higher evaporation and why?
When MgCO3(s) is strongly heated, it produces solid MgO as gaseous CO2 is driven off.Does the oxidation number of carbon change upon the formation of CO2?
A solution of hydrogen peroxide, H2O2, is titrated with potassium permanganate, KMnO4, according to the following equation: 5H2O2 + 2KMnO4 + 3H2SO4 = 5O2 + 2MnSO4 + 8H2O + K2SO4. It requires 46.0 mL of 0.145 Mol/L KMnO4 to titrate 50.0 mL of the solution of H2O2. What is the mole per liter concentration of H2O2 in the solution?
Which chemical equation best describes the reaction of potassium metal with fluorine gas to form solid potassium fluoride? A. K(s) + F2(g) → KF2(s) B. K(s) + F(g) → KF(s) C. K2(g) + F2(g) → 2 KF(s) D. 2 K(s) + F2(g) → 2 KF(s) I guessed B
Heat is released when H2 gas and O2 gas react to form H2O. Why? A. Breaking the H–H bond in H2 gas releases heat. B. Breaking the O–O bond in O2 gas releases heat. C. Forming the H–O bonds in H2O releases heat. D. Both A and B are responsible for heat being released in the reaction. I guessed D
How many moles of water (H2O) would be produced if 10 moles of O2 gas reacted completely with excess H2 gas?2 H2(g) + O2(g) → 2 H2O(g)A. 5 B. 10 C. 20 D. 30
Which energy conversion must occur in an operating electrolytic cell? (1) electrical energy to chemical energy (2) electrical energy to nuclear energy (3) chemical energy to electrical energy (4) chemical energy to nuclear energy
Which condensed structural formula represents an unsaturated compound? (1) CH3CHCHCH3 (3) CH3CH3 (2) CH3CH2CH3 (4) CH4
The accepted value for the percent by mass of water in a hydrate is 36.0%. In a laboratory activity, a student determined the percent by mass of water in the hydrate to be 37.8%. What is the percent error for the student's measured value? (1) 5.0% (3) 1.8% (2) 4.8% (4) 0.05%
Which compounds are classified as Arrhenius acids? (1) HCl and NaOH (2) HNO3 and NaCl (3) NH3 and H2CO3 (4) HBr and H2SO4
Which quantity can be calculated for a solid compound, given only the formula of the compound and the Periodic Table of the Elements? (1) the density of the compound (2) the heat of fusion of the compound (3) the melting point of each element in the compound (4) the percent composition by mass of each element in the compound
