P me have no brain please help I just wanna get through the year According to the law of conservation of mass, what is the mass of sodium oxide (Na20) formed in this reaction? 4Na 91.96 g 02 32.00 g 2Na 0 ?

A. 247.92 grams

B. 123.96 grams

C. 61.68 grams

D. 495.84 grams​

(a) calculate the number of electrons in a small, electrically neutral silver pin that has a mass of 10.0 g. silver has 47 electrons per atom, and its molar mass is 107.87 g/mol. (b) imagine adding electrons to the pin until the negative charge has the very large value 1.00 mc. how many electrons are added for every 109 electrons already present

Asled is being held at rest on a slope that makes an angle θ with the horizontal. after the sled is released, it slidesa distance d1 down the slope and then covers the distance d2 alongthe horizontal terrain before stopping. find the coefficient ofkinetic friction μk between the sled and the ground, assumingthat it is constant throughout the trip. find the coefficient of kinetic frictionμk. express your answer in terms of someor all of the variables d1, d2, and θ.

What is similar between metals and suspensions