EdEarl

yw

Welcome Kagen, enjoy.

The atomic mass as I suggested would be the average for that crystal, imo.

Copper and Zinc do not form a molecule AFAIK; rather, they combine in a crystal structure. When a sample is measured by a mass spectrometer, it would have about 10 times as many copper as zinc atoms and the measured atomic weight would be either the atomic weight of Cu and atomic weight of Zn or a combination of the two as if they were a molecule. I'm not sure. Imatfaal will know and should tell us. I am also going on the way you were originally trying to solve the problem by balancing a chemical equation, since you were in lecture, not me, I'm assuming you know something about what your instructor wants.

9.457*10^-2 mol Cu 9.789*10^-3 mol Zn 10:1 more or less. Kinda like Cu10Zn, you can calculate a better ratio. So the atomic mass would be about 10 (your calculation) Cu atomic masses + 1 Zn atomic mass. If that's wrong, I'm sure Imatfaal will tell us.

That's right, sorry about that.

How many of each?

We should find out relatively how may atoms of Cu and Zn exist in the sample. If it is 1:1 then Cu+Zn = CuZn, if it is 2:1, then Cu2Zn, or whatever. Though, I think we can calculate the atomic mass whatever the ratio.

IMO it is much better today than for the past few weeks, TYVM for fixing.

No, you need to know how many moles of Cu and how many of Zn.

Yes, what is the answer for Cu in the mixture of Cu and Zn? Same problem, different numbers, different things. Cu instead of flour, Zn instead of salt.

If I have 3 grams of flour and salt in a mixing bowl and 1 gram is salt, how many grams of flour? It isn't a chemistry equation.

How many grams of Cu in the 6.01 Cu contaminated with Zn? Would Cu combining with Zn to make a Cu and Zn molecule change the number of grams?

Sounds like you are on the right track, show some steps toward the solution.

Response is very good at this moment.

YW

In the table you provided the _ character means space, not "_", and space is 2016 (0x20 = 001000002).

Here are a couple of links to ASCII. Think of ASCII (any character code) as a cipher that converts character icons into binary numbers that the computer can store and use. There is nothing inside a computer except numbers, regardless of how the magic of software makes it look like computers contain videos, pictures, text, etc; everything is converted into numbers that a computer can process. http://en.wikipedia.org/wiki/Ascii http://en.wikipedia.org/wiki/Extended_ASCII http://www.asciitable.com/

Same here, both Firefox and Internet Explorer.

The documentary, High Tech Low Life, is about two of China's citizen reporters or social commentary bloggers, who risk imprisonment to tell China and the world about government failures and corruption. It gives insight what it is like for some people who live in China. And, it tells us that the workings of the Chinese government are not only mysterious to us outsiders, but also to the Chinese people. The documentary also tells us that social commentary bloggers are ubiquitous and unstoppable, and they are changing the Chinese government and forcing it to be more open. But, they are only at the beginning of a long hard road. High Tech Low Life is on Netflix, or you can purchase a DVD at http://hightechlowlifefilm.com/.

Z, since you are being solipsistic in my world, perhaps you should reexamine your premise about the car.

LOL Sorry Z, your car doesn't sit still, even with the engine turned off and wheels blocked, because the Earth rotates and orbits the Sun, the Sun orbits the galaxy, and the galaxy is moving relative to other galaxies. Each molecule and atom in your car move, because they are at a temperature above absolute zero. This is a science forum, and everything moves. Except, maybe, some rigid people who post here.

The article also says that if one of these objects was orbiting a star, it would probably be called a planet. Thus, a star just slightly larger than one of these cool brown dwarfs orbiting with a cool brown dwarf, will probably be called a star and planet. Since the two can be fairly close in size, they may orbit each other with the center of rotation being outside both of them. IMO it is not a non-star orbiting a star, but that's just my opinion.

Generally a person needs two things from an education: 1) credentials 2) a love for learning. Credentials are needed to get a job. A love for learning is needed to understand how to live and how to enjoy life. To understand how to live and enjoy life, one needs more than rote learning of facts and processes necessary to get a job; one needs to know about the arts, sciences and philosophy. Ones formal education from first grade through high school, technical school or university is mostly about getting credentials for a career. In this culture, that means spending lots of time learning rote facts, which is often boring. Unfortunately, this learning process can create a hate for learning rather than a love of learning, and educators and their administrators need to improve their methods in some cases. If you survive and get credentials and still love learning, you can always study the arts, sciences and/or philosophy to learn how to live a better, happier life. Live well and prosper.

NASA is government, which has no economic interest in efficiency. It isn't that they willfully keep costs high, they just do it from lack of focus. They have been hammered several times on safety after shuttle crashes; thus, their focus has been to improve safety, whatever the cost. Safety is better; costs be dammed. What economical Single-Stage Orbiters have been developed? Please give references. Elon Musk seems to have the best program for developing reusable-thus-inexpensive rockets. And, he hopes to cut the cost of Earth-to-LEO by 100. If he comes anywhere close to that 1:100 reduction, it will be good. SpaceX already uses a two stage system to deliver supplies to the ISS, not a single-stage to orbit system. They already claim lower costs; although, they have not perfected their reusable booster.