ColorChange.cs

using UnityEngine;
using System.Collections.Generic;

[System.Serializable]
public struct ColorMapping
{
    public KeyCode KeyCode;
    public Color Color;
}

[RequireComponent(typeof(Renderer))]
public class ColorChange : MonoBehaviour
{
    public List<ColorMapping> ColorMappings = new List<ColorMapping>();

    private new Renderer renderer;

    private void Awake ()
    {
        renderer = GetComponent<Renderer>();
    }

    private void Update ()
    {
        foreach (var colorMapping in ColorMappings)
        {
            if (Input.GetKeyDown(colorMapping.KeyCode))
            {
                renderer.material.color = colorMapping.Color;
                break;
            }
        }
    }
}