Urgent help plsss a stock solution of 2M NaOH was prepared by dissolving 4g NaOH in 50cm³ of distilled water. 10cm³ of the stock solution was put into a measuring cylinder and then diluted with different amount of distilled water to 15cm³. determine the volume of distilled water used to dilute the solution. Calculate the concentration of the solution in mol/dm³ and g/dm³​

What is the temperature of one mole of helium gas at stp?

Which explanation is true about what happens to a ray of light when it strikes a mirror? a. a light ray is transmitted toward a mirror at a certain angle. the light ray is then reflected by the mirror at an equal angle but in the opposite direction of the transmitted ray. b. an incident ray strikes a mirror at an angle with a line perpendicular to the mirror. the light ray is then reflected at an angle equal to the angle of incidence but on the opposite side of the perpendicular line. c. a reflecting ray strikes a mirror at an angle with a line perpendicular to the mirror. the light ray is then refracted at an angle equal to the angle of the reflecting ray and on the same side of the perpendicular line. d. an incident ray strikes a mirror at an angle with a line parallel to the mirror. the light ray is then transmitted at an angle equal to the angle of incidence but on the opposite side of the parallel line. you so much! : -d take the time to try and answer correctly.

If 22.5 liters of oxygen reacted with excess of hydrogen, how many liters of water vapor could be produced?