VincenTragosta - Tanya, Jawab, dan Belajar Tanpa Batas Logo

Questions in chemistry

[Terjawab] What happens to the potential energy of the molecules in a reaction? A. The reactants only lose potential energy when forming products. B. The potential energy of the products is equal to that of the reactants. C. The potential energy of the molecules does not change in a reaction. D. The potential energy of the molecules changes during a reaction.

[Terjawab] Which answer below correctly identifies the type of change and the explanation for the boiling of water? A. physical change because even though the change caused the temperature of the water to increase, the water's physical properties remained exactly the same B. physical change because even though gas formation was observed, the water was undergoing a state change, which means that its original properties are preserved C. chemical change because gas formation was observed, which indicated that the water was transformed into a different substance D. chemical change because a temperature change was observed, which indicated that the water was transformed into a different substance

[Terjawab] What are synthetic polymers NOT made out of? A. Oil B. Coal C. Natural Gas D. Organic Fibers

[Terjawab] How many oxygen atoms are there in the following compound: 2HNO

[Terjawab] Now that we have put a coefficient of 2 in front of $NaNO _3$, what coefficient should go in front of $PbCl _2$ to balance lead $( Pb )$ ? $Pb(NO_3)_2+NaCl \rightarrow ? PbCl_2+2 NaNO_3$ Express your answer numerically as an integer.

[Terjawab] Which chemical symbol represents a metalloid? A. B B. Al C. Ga D. Zn E. Ar

[Terjawab] Which is a substance that is made up of only one type of atom? A. compound B. element C. solution D. mixture

[Terjawab] What would happen to the rate of a reaction with rate law rate $=k[ NO ]^2\[ H _2\]$ if the concentration of NO were halved? A. The rate would be doubled. B. The rate would be four times larger. C. The rate would be one-fourth. D. The rate would also be halved.

[Terjawab] Which property describes a mixture? A. It cannot be separated by physical methods. B. It has a single chemical composition. C. It cannot have more than one state of matter. D. It cannot be described by a chemical symbol or formula.

[Terjawab] Which represents the balanced nuclear equation for the beta plus decay of C-11? ${ }_6^{11} C \longrightarrow{ }_5^{11} B+{ }_{+1}^0 e$ ${ }_6^{11} C \longrightarrow{ }_7^{11} N+{ }_{+1}^0 e$ ${ }_6^{11} C \longrightarrow{ }_7^{11} N+{ }_{-1}^0 e$ ${ }_6^{11} C \longrightarrow{ }_5^{11} B+{ }_{-1}^0 e