In solid methane, the forces between the neighboring CH4 molecules are best characterized as

In solid methane, the forces between the neighboring CH4 molecules are best characterized as a. ionic b. covalent c. hydrogen d. ion-ion e. London (dispersion) forces Answer and Explanation: In order for us to identify the type of correct intermolecular forces, we need to first identify what kind of molecule CH4 is. Ionic forces are present in ionic compounds. Ionic compounds have a metal with a nonmetal or a metal with a polyatomic ion. In CH4, both atoms are nonmetal (covalent), and therefore it is not an ionic compound. Covalent bonds are actual bonds between the atoms of a molecule and are not intermolecular forces. Hydrogen bonds are intermolecular forces present in molecules that have

Individuals benefit from arts based groups.

According to sciencedaily.com, a new study found that both healthy adults and those experiencing mental health conditions who participate in arts-based groups such as creative writing or choir benefit greatly benefit from them. Those who participate in these groups reported a significant increase in positive emotions and a significant decrease in negative emotions. Adults with chronic mental health conditions were equally able to derive emotional benefits as healthy adults. It is amazing because this kind of therapeutic activity does not involve any prescriptions with side effects, but rather the power of creativity and socialization. "The findings of this study are exciting because they cl

Which substance has nonpolar covalent bonds?

Which substance has nonpolar covalent bonds? (1) Cl2 (2) SO3 (3) SiO2 (4) CCl4 Answer and Explanation: Covalent bonds are formed between 2 or more nonmetals. Looking at the answer choices, we can see that all of the answers have nonmetals, and therefore all have covalent bonds. The molecule that is composed of the same 2 elements has non polar covalent bonds since if the elements are the same they have the same electronegativities and share electrons in the bond equally. Looking at the answer choices, we can see that choice (1) Cl2 is the right answer since the molecule is composed of two chlorines. To find out more about our amazing chemistry tutors in NYC and online, please visit us here.

Two Common Math Mistakes on MCAT Physics

Physics plays a relatively minor role in the new MCAT. In fact, only one quarter of the questions on the Chemistry/Physics section actually test general physics knowledge. From my experience teaching MCAT physics, many mistakes people make on this section of the exam are due to errors in mathematical reasoning rather than physics content knowledge. Two common mistakes include: Units When carrying out calculations on the MCAT, be mindful of the units attached to each variable. Topics like hydrostatic pressure and buoyancy, for example, often require equations involving density. In general chemistry class, we learned that the density of water is 1 g/mL. However, on the MCAT density of water is

What is the difference between a ketone and aldehyde?

Ketone and aldehydes are functional groups that organic compounds have. A ketone is C=O that is connected to a carbon on both sides. Therefore it is always found inside a chain and never at the end. Aldehyde, on the other hand is C=O that is connected to a carbon on one side and hydrogen on another. Therefore, aldehydes are found at the end of chains. To learn more organic chemistry and schedule a free consultation with the best organic chemistry tutors in NYC or online, click here. #organicchemistry

The pH of a solution is 7. When acid is added to the solution, the hydronium ion concentration becom

The pH of a solution is 7. When acid is added to the solution, the hydronium ion concentration becomes 100 times greater. What is the pH of the new solution? (1) 1 (2) 5 (3) 9 (4) 14 Answer and Explanation: First we need to understand the pH scale well. If pH less than 7, the solution is acid, equal to 7 is neutral and greater than 7 is basic. When acid is added to the solution, it should become more acidic and therefore have a lower pH.Every time the concentration of Hydrogen ion increases by 10, that equal to going 1 unit down on the pH scale. Therefore if the hydrogen ion concentration increases by 100, the pH of the solution should be 2 units lower than the original ph. 7-2= 5. The new p

Under which transformation would A B C , the image of ABC, not be congruent to ABC?

Under which transformation would A B C , the image of ABC, not be congruent to ABC? (1) reflection over the y-axis (2) rotation of 90o clockwise about the origin (3) translation of 3 units right and 2 units down (4) dilation with a scale factor of 2 centered at the origin Explanation and answer: The only transformation listed that changes the size of ABC is dilation, choice (4). Under dilation with a scale of 2, ABC will be double the size of the original and therefore not be congruent. Other transformations such as reflection, rotation and translation just change the location of ABC but not its size. To have a session with amazing geometry tutor in NYC or online, contact us here. #geomet

What is the charge of the nucleus of a copper atom?

(1) +1 (2) +2 (3) +29 (4) +64 Answer and explanation: What particles are inside the nucleus of an atom? Protons and neutrons. Protons have a charge of plus one while neutrons have no charge (neutral). Therefore, the charge of nucleus of copper atom must be equal to the charge of the protons inside the nucleus. How many protons does Copper have? The number of protons is equal to atomic number which we can find by looking at the periodic table. This number is located on the bottom left corner of each symbol. If we look at the periodic table, we will see that its atomic number is 29. Therefore the charge of the nucleus is +29, choice (3). Call 646-407-9078 to scheduler a session with an amazin

Which of the following aqueous solutions has the lowest freezing point?

Which of the following aqueous solutions has the lowest freezing point? (A) 0.2 m NaCl (B) 0.2 m CaCl2 (C) 0.2 m H2SO4 (D) 0.2 m NH3 (E) 0.2 m Al(NO3)3 Answer and Explanation: Freezing point of a pure solvent depends on the amount of solute that gets dissolved in it. In order to determine which solution has the lowest freezing point, we need to look at the molality as well as whether the solute is ionic or covalent. Since the molality is equal for all of the answer choices, we need to look at what kind of solutes are present. Choice A: NaCl is ionic since it has a metal and a nonmetal. NaCl dissociates into 2 ions: Na+ and Cl - Choice B: CaCl2 is ionic since it has a metal and a nonmetal.

Under which of the following conditions can an endothermic reaction be thermodynamically favorable?

Under which of the following conditions can an endothermic reaction be thermodynamically favorable? (A) ΔG is positive (B) ΔS is negative (C) TΔS > ΔH (D) TΔS = 0 (E) There are no conditions under which an endothermic reaction can be thermodynamically favorable. Answer and explanation: To be thermodynamically favorable, a reaction must have negative ΔG (Gibbs Free Energy). The formula for Gibbs Free Energy is ΔG = ΔH - TΔS where ΔS is entropy and ΔH is enthalpy. Since the question says that the reaction is endothermic, we know right away that ΔH is positive. Therefore, in order for ΔG to be negative, ΔS must be positive and temperature must be high enough to overcome the positive ΔH. Choice

Solid Al(NO3)3 is added to distilled water to produce a solution

Solid Al(NO3)3 is added to distilled water to produce a solution in which the concentration of nitrate, [NO3-], is 0.10 M. What is the concentration of aluminum ion, [Al3+], in this solution? (A) 0.010 M (B) 0.033 M (C) 0.066 M (D) 0.10 M (E) 0.30M Answer and Explanation: Looking at the formula Al(NO3)3, we notice that for 1 Al ion, there are 3 NO3 ions. Therefore when aluminum nitrate dissociates in water, it produces 1 aluminum ion and 3 nitrate ions per each formula unit. Since we know the concentration of nitrate is 0.1, the concentration of aluminum should be 1/3 of that. 0.1 (1/3) = 0.033 M (B) Let our amazing chemistry tutor help you in NYC and online. We love to share our passion for

Algebra 2 regent question

Given i is the imaginary unit, (2- yi)^2 in simplest form is In order to do this problem, we have to remember just one simple rule: i ^2 = -1 To solve the problem we first can distribute the terms (2- yi)^2 = (2-yi) (2-yi) = 4 - 2yi - 2yi + (y^2)(i^2 )= 4 - 4yi - y^2 Remember that i^2 = -1 and therefore (y^2)(i^2 ) becomes simply -y^2 Working with imaginary numbers might seem scary at first, but its nothing other than algebra we are already used to with the knowledge that i squared is equal to negative one. To find an amazing math tutor in NYC or online, please contact us here. #algebra

Strategy for the MCAT’s Critical Analysis and Reasoning Section

The writers of the MCAT assert that its critical analysis and reasoning section, also known as CARS, tests three skills – comprehension, reasoning “within the text,” and reasoning “beyond the text.” Comprehension questions may ask, for example, about the overall theme of the passage or the meaning of particular words in context. Reasoning questions, by contrast, challenge the test-taker to analyze and evaluate the author’s argument and even extrapolate the author’s ideas into new contexts. Wedged in between the chemistry/physics and biology/biochemistry sections, CARS forces test-takers to adeptly switch from scientific reasoning to critical reasoning and then back again. Reasoning skills no