Which one of the following equations is properly balanced? a. CH 3CHO + 3O 2 → 2CO 2 + 2H 2O b. NH 4NO 3 → 2H 2O + N 2 c. Na 2CO 3 + 2H 2SO 4 → Na 2SO 4 + 2H 2O + CO 2 d. 2Na 2SO 4 + 3Bi(NO 3) 3 → Bi 2(SO 4) 3 + 9NaNO 3 e. Sn + 4HNO 3 → SnO 2 + 4NO 2 + 2H 2O

The chemical equation that is properly balanced is;

e. Sn + 4HNO₃ → SnO₂ + 4NO₂ + 2H₂O

Explanation:

To solve the question, we note the reactions thus and we look for a reason why the reaction is not balanced as follows.

a. CH₃CHO + 3O₂ → 2CO₂ + 2H₂O

Here we have 7 oxygen atoms in the reactant and 6 in the products

Not balanced

b. NH₄NO₃ → 2H₂O + N₂

Here we have three oxygen in the reactant and four in the products = Not balanced

c. Na₂CO₃ + 2H₂SO₄ → Na₂SO₄ + 2H₂O + CO₂

Here we have 11 oxygen atoms in the reactant and 8 in the products = Not balanced

d. 2Na₂SO₄ + 3Bi(NO₃)₃ → Bi₂(SO 4)₃ + 9NaNO₃

Here  we have 2 Na in the reactants and 9 Na in the products = Not balanced

e. Sn + 4HNO₃ → SnO₂ + 4NO₂ + 2H₂O

Here we have equal number of products and reactants = Balanced chemcal reaction equation.

question: ray weighs 100 kilograms, his wrestling partner, bobby, weighs 50 kilograms. if ray moves at 4 m s , how fast will bobby have to run at him to apply an equal amount of kinetic energy?

answer: 8 m/s he needs to run twice as fast to keep up so he has some work to do

explanation:   if the mass has units of kilograms and the velocity of meters per second, the kinetic energy has units of kilograms-meters squared per second squared.

question answered by

(jacemorris04)

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.